Merge feature/v1.3.2-lint-cleanup into main

- Complete lint cleanup (Phase 1-7)
- Replace magic numbers with constants
- Remove unused imports/members
- Add Logger.w() for swallowed exceptions
- Custom SyncException for better error handling
- ConstructorParameterNaming with @SerializedName
- ReturnCount & Destructuring with @Suppress
- F-Droid: Add privacy notice for file logging
- Update docs (FEATURES.md, README.md)
- Add fastlane changelogs for versionCode 10

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,152 @@
+name: 🐛 Bug Report / Fehlerbericht
+description: Melde einen Fehler in der App / Report a bug in the app
+title: "[BUG] "
+labels: ["bug"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Danke für deinen Bug Report! / Thanks for reporting a bug!
+        
+        Bitte fülle alle relevanten Felder aus. / Please fill out all relevant fields.
+
+  - type: textarea
+    id: description
+    attributes:
+      label: 🐛 Beschreibung / Description
+      description: Beschreibe den Fehler kurz und präzise / Describe the bug briefly and precisely
+      placeholder: "z.B. Auto-Sync funktioniert nicht mehr nach App-Update / e.g. Auto-sync stopped working after app update"
+    validations:
+      required: true
+
+  - type: dropdown
+    id: android-version
+    attributes:
+      label: 📱 Android Version
+      description: Welche Android Version verwendest du? / Which Android version are you using?
+      options:
+        - Android 14
+        - Android 13
+        - Android 12
+        - Android 11
+        - Android 10
+        - Android 9
+        - Android 8.1
+        - Android 8.0
+        - Andere / Other
+    validations:
+      required: true
+
+  - type: input
+    id: app-version
+    attributes:
+      label: 📲 App Version
+      description: Welche Version der App verwendest du? (Einstellungen → Über) / Which app version? (Settings → About)
+      placeholder: "z.B. / e.g. v1.1.0"
+    validations:
+      required: true
+
+  - type: input
+    id: device
+    attributes:
+      label: 📱 Gerät / Device
+      description: Welches Gerät verwendest du? / Which device are you using?
+      placeholder: "z.B. Samsung Galaxy S21, Google Pixel 7, etc."
+    validations:
+      required: false
+
+  - type: textarea
+    id: steps
+    attributes:
+      label: 🔄 Schritte zum Reproduzieren / Steps to Reproduce
+      description: Wie kann der Fehler reproduziert werden? / How can the bug be reproduced?
+      placeholder: |
+        1. Öffne die App / Open the app
+        2. Gehe zu Einstellungen / Go to settings
+        3. Klicke auf ... / Click on ...
+        4. Fehler tritt auf / Bug occurs
+    validations:
+      required: true
+
+  - type: textarea
+    id: expected
+    attributes:
+      label: ✅ Erwartetes Verhalten / Expected Behavior
+      description: Was sollte passieren? / What should happen?
+      placeholder: "z.B. Notizen sollten alle 30 Min synchronisiert werden / e.g. Notes should sync every 30 min"
+    validations:
+      required: true
+
+  - type: textarea
+    id: actual
+    attributes:
+      label: ❌ Tatsächliches Verhalten / Actual Behavior
+      description: Was passiert stattdessen? / What happens instead?
+      placeholder: "z.B. Sync funktioniert nicht, keine Notification / e.g. Sync doesn't work, no notification"
+    validations:
+      required: true
+
+  - type: dropdown
+    id: sync-enabled
+    attributes:
+      label: <EFBFBD> Auto-Sync aktiviert? / Auto-Sync enabled?
+      options:
+        - "Ja / Yes"
+        - "Nein / No"
+    validations:
+      required: false
+
+  - type: dropdown
+    id: battery-optimization
+    attributes:
+      label: 🔋 Akku-Optimierung deaktiviert? / Battery optimization disabled?
+      description: Einstellungen → Apps → Simple Notes → Akku → Nicht optimieren / Settings → Apps → Simple Notes → Battery → Don't optimize
+      options:
+        - "Ja, deaktiviert / Yes, disabled"
+        - "Nein, noch optimiert / No, still optimized"
+        - "Weiß nicht / Don't know"
+    validations:
+      required: false
+
+  - type: textarea
+    id: server-config
+    attributes:
+      label: 🌐 Server-Konfiguration / Server Configuration
+      description: Falls relevant / If relevant (KEINE Passwörter! / NO passwords!)
+      placeholder: |
+        - Server läuft lokal / Server runs locally
+        - Docker auf Raspberry Pi / Docker on Raspberry Pi
+        - Gleiche WiFi / Same WiFi
+        - Server-IP: 192.168.x.x (erste 3 Zahlen reichen / first 3 numbers sufficient)
+    validations:
+      required: false
+
+  - type: textarea
+    id: logs
+    attributes:
+      label: 📋 Logs / Screenshots
+      description: |
+        Falls vorhanden: Screenshots oder LogCat Output / If available: Screenshots or LogCat output
+        
+        LogCat Filter: `adb logcat -s SyncWorker NetworkMonitor WebDavSyncService`
+      placeholder: "Füge hier Logs oder Screenshots ein / Paste logs or screenshots here"
+    validations:
+      required: false
+
+  - type: textarea
+    id: additional
+    attributes:
+      label: 🔧 Zusätzliche Informationen / Additional Context
+      description: Gibt es noch etwas, das wir wissen sollten? / Is there anything else we should know?
+    validations:
+      required: false
+
+  - type: checkboxes
+    id: checklist
+    attributes:
+      label: ✅ Checklist
+      options:
+        - label: Ich habe die [Troubleshooting-Sektion](https://github.com/inventory69/simple-notes-sync/blob/main/QUICKSTART.md#troubleshooting) gelesen / I have read the troubleshooting section
+          required: false
+        - label: Ich habe "Verbindung testen" in den Einstellungen probiert / I have tried "Test connection" in settings
+          required: false

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,11 @@
+blank_issues_enabled: true
+contact_links:
+  - name: 📖 Dokumentation / Documentation
+    url: https://github.com/inventory69/simple-notes-sync/blob/main/README.md
+    about: Schau zuerst in die Dokumentation / Check documentation first
+  - name: 🚀 Quick Start Guide
+    url: https://github.com/inventory69/simple-notes-sync/blob/main/QUICKSTART.md
+    about: Schritt-für-Schritt Anleitung / Step-by-step guide
+  - name: 🐛 Troubleshooting
+    url: https://github.com/inventory69/simple-notes-sync/blob/main/QUICKSTART.md#troubleshooting
+    about: Häufige Probleme und Lösungen / Common issues and solutions

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,84 @@
+name: 💡 Feature Request / Feature-Wunsch
+description: Schlage eine neue Funktion vor / Suggest a new feature
+title: "[FEATURE] "
+labels: ["enhancement"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Danke für deinen Feature-Vorschlag! / Thanks for your feature suggestion!
+
+  - type: textarea
+    id: feature-description
+    attributes:
+      label: 💡 Feature-Beschreibung / Feature Description
+      description: Was möchtest du hinzugefügt haben? / What would you like to be added?
+      placeholder: "z.B. Notizen sollten Markdown-Formatierung unterstützen / e.g. Notes should support markdown formatting"
+    validations:
+      required: true
+
+  - type: textarea
+    id: problem
+    attributes:
+      label: 🎯 Problem / Motivation
+      description: Welches Problem würde dieses Feature lösen? / What problem would this feature solve?
+      placeholder: "z.B. Ich möchte Code-Snippets und Listen in meinen Notizen formatieren / e.g. I want to format code snippets and lists in my notes"
+    validations:
+      required: true
+
+  - type: textarea
+    id: solution
+    attributes:
+      label: 📝 Vorgeschlagene Lösung / Proposed Solution
+      description: Wie könnte das Feature funktionieren? / How could the feature work?
+      placeholder: "z.B. Markdown-Editor mit Live-Preview / e.g. Markdown editor with live preview"
+    validations:
+      required: false
+
+  - type: textarea
+    id: alternatives
+    attributes:
+      label: 🔄 Alternativen / Alternatives
+      description: Hast du andere Lösungsansätze in Betracht gezogen? / Have you considered other solutions?
+    validations:
+      required: false
+
+  - type: dropdown
+    id: platform
+    attributes:
+      label: 📱 Plattform / Platform
+      description: Für welche Komponente ist das Feature? / For which component is the feature?
+      options:
+        - Android App
+        - WebDAV Server
+        - Dokumentation / Documentation
+        - Andere / Other
+    validations:
+      required: true
+
+  - type: dropdown
+    id: priority
+    attributes:
+      label: 🌟 Priorität (aus deiner Sicht) / Priority (from your perspective)
+      options:
+        - Nice to have
+        - Wichtig / Important
+        - Sehr wichtig / Very important
+    validations:
+      required: false
+
+  - type: checkboxes
+    id: willing-to-contribute
+    attributes:
+      label: 🤝 Beitragen / Contribute
+      options:
+        - label: Ich würde gerne bei der Implementierung helfen / I would like to help with implementation
+          required: false
+
+  - type: textarea
+    id: additional
+    attributes:
+      label: 🔧 Zusätzliche Informationen / Additional Context
+      description: Screenshots, Mockups, Links, ähnliche Apps, etc.
+    validations:
+      required: false

.github/ISSUE_TEMPLATE/question.yml

@@ -0,0 +1,76 @@
+name: ❓ Question / Frage
+description: Stelle eine Frage zur Nutzung / Ask a question about usage
+title: "[QUESTION] "
+labels: ["question"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Hast du eine Frage? Wir helfen gerne! / Have a question? We're happy to help!
+
+  - type: textarea
+    id: question
+    attributes:
+      label: ❓ Frage / Question
+      description: Was möchtest du wissen? / What would you like to know?
+      placeholder: "z.B. Wie kann ich die Sync-URL für einen externen Server konfigurieren? / e.g. How can I configure the sync URL for an external server?"
+    validations:
+      required: true
+
+  - type: checkboxes
+    id: documentation-checked
+    attributes:
+      label: 📚 Dokumentation gelesen / Documentation checked
+      description: Hast du bereits in der Dokumentation nachgeschaut? / Have you already checked the documentation?
+      options:
+        - label: Ich habe die [README](https://github.com/inventory69/simple-notes-sync/blob/main/README.md) gelesen / I have read the README
+          required: false
+        - label: Ich habe den [Quick Start Guide](https://github.com/inventory69/simple-notes-sync/blob/main/QUICKSTART.md) gelesen / I have read the Quick Start Guide
+          required: false
+        - label: Ich habe das [Troubleshooting](https://github.com/inventory69/simple-notes-sync/blob/main/QUICKSTART.md#troubleshooting) durchgearbeitet / I have checked the troubleshooting section
+          required: false
+
+  - type: textarea
+    id: tried
+    attributes:
+      label: 🔍 Was hast du bereits versucht? / What have you already tried?
+      description: Hilf uns, dir besser zu helfen / Help us help you better
+      placeholder: "z.B. Ich habe versucht die Server-URL anzupassen, aber... / e.g. I tried adjusting the server URL, but..."
+    validations:
+      required: false
+
+  - type: dropdown
+    id: topic
+    attributes:
+      label: <EFBFBD> Thema / Topic
+      description: Um was geht es? / What is this about?
+      options:
+        - Server Setup / Server-Einrichtung
+        - App-Konfiguration / App configuration
+        - Sync-Probleme / Sync issues
+        - Netzwerk / Network
+        - Android-Einstellungen / Android settings
+        - Andere / Other
+    validations:
+      required: false
+
+  - type: textarea
+    id: context
+    attributes:
+      label: <EFBFBD> Kontext / Context
+      description: Zusätzliche Informationen die hilfreich sein könnten / Additional information that might be helpful
+      placeholder: |
+        - Android Version: Android 13
+        - App Version: v1.1.0
+        - Server: Raspberry Pi mit Docker / Raspberry Pi with Docker
+        - Netzwerk: Lokales WiFi / Local WiFi
+    validations:
+      required: false
+
+  - type: textarea
+    id: additional
+    attributes:
+      label: 🔧 Screenshots / Config
+      description: Falls hilfreich (KEINE Passwörter!) / If helpful (NO passwords!)
+    validations:
+      required: false

.github/workflows/build-production-apk.yml

@@ -2,11 +2,11 @@ name: Build Android Production APK
 
 on:
   push:
-    branches: [ main ]  # Trigger on push to main branch
+    branches: [ main ]  # Nur bei Push/Merge auf main triggern
-  workflow_dispatch:  # Allow manual trigger
+  workflow_dispatch:  # Ermöglicht manuellen Trigger
 
 permissions:
-  contents: write  # Required for creating releases
+  contents: write  # Fuer Release-Erstellung erforderlich
 
 jobs:
   build:
@@ -14,185 +14,138 @@ jobs:
     runs-on: ubuntu-latest
     
     steps:
-      - name: Checkout code
+      - name: Code auschecken
         uses: actions/checkout@v4
       
-      - name: Setup Java
+      - name: Java einrichten
         uses: actions/setup-java@v4
         with:
           distribution: 'temurin'
           java-version: '17'
       
-      - name: Generate Production version number
+      - name: Semantic Versionsnummer aus build.gradle.kts extrahieren
         run: |
-          # Generate semantic version: YYYY.MM.DD
+          # Version aus build.gradle.kts fuer F-Droid Kompatibilität
-          VERSION_NAME="$(date +'%Y.%m.%d')"
+          VERSION_NAME=$(grep "versionName = " android/app/build.gradle.kts | sed 's/.*versionName = "\(.*\)".*/\1/')
+          VERSION_CODE=$(grep "versionCode = " android/app/build.gradle.kts | sed 's/.*versionCode = \([0-9]*\).*/\1/')
           
-          # Use GitHub run number as build number for production
+          # Semantische Versionierung (nicht datums-basiert)
-          BUILD_NUMBER="${{ github.run_number }}"
+          BUILD_NUMBER="$VERSION_CODE"
           
           echo "VERSION_NAME=$VERSION_NAME" >> $GITHUB_ENV
           echo "BUILD_NUMBER=$BUILD_NUMBER" >> $GITHUB_ENV
-          echo "VERSION_TAG=v$VERSION_NAME-prod.$BUILD_NUMBER" >> $GITHUB_ENV
+          echo "VERSION_TAG=v$VERSION_NAME" >> $GITHUB_ENV
           
-          echo "🚀 Generated PRODUCTION version: $VERSION_NAME+$BUILD_NUMBER"
+          echo "🚀 Baue Version: $VERSION_NAME (Code: $BUILD_NUMBER)"
       
-      - name: Update build.gradle.kts with Production version
+      - name: Version aus build.gradle.kts verifizieren
         run: |
-          # Update versionCode and versionName in build.gradle.kts
+          echo "✅ Verwende Version aus build.gradle.kts:"
-          sed -i "s/versionCode = [0-9]*/versionCode = ${{ env.BUILD_NUMBER }}/" android/app/build.gradle.kts
-          sed -i "s/versionName = \".*\"/versionName = \"${{ env.VERSION_NAME }}\"/" android/app/build.gradle.kts
-          
-          echo "✅ Updated build.gradle.kts:"
           grep -E "versionCode|versionName" android/app/build.gradle.kts
       
-      - name: Setup Android signing
+      - name: Android Signing konfigurieren
         run: |
           echo "${{ secrets.KEYSTORE_BASE64 }}" | base64 -d > android/app/simple-notes-release.jks
           echo "storePassword=${{ secrets.KEYSTORE_PASSWORD }}" > android/key.properties
           echo "keyPassword=${{ secrets.KEY_PASSWORD }}" >> android/key.properties
           echo "keyAlias=${{ secrets.KEY_ALIAS }}" >> android/key.properties
           echo "storeFile=simple-notes-release.jks" >> android/key.properties
-          echo "✅ Signing configuration created"
+          echo "✅ Signing-Konfiguration erstellt"
       
-      - name: Build Production APK (Release)
+      - name: Produktions-APK bauen (Standard + F-Droid Flavors)
         run: |
           cd android
-          ./gradlew assembleRelease --no-daemon --stacktrace
+          ./gradlew assembleStandardRelease assembleFdroidRelease --no-daemon --stacktrace
       
-      - name: Copy APK variants to root with version names
+      - name: APK-Varianten mit Versionsnamen kopieren
         run: |
           mkdir -p apk-output
           
-          # Universal APK
+          # Standard Flavor - Universal APK
-          cp android/app/build/outputs/apk/release/app-universal-release.apk \
+          cp android/app/build/outputs/apk/standard/release/app-standard-release.apk \
-             apk-output/simple-notes-sync-v${{ env.VERSION_NAME }}-universal.apk
+             apk-output/simple-notes-sync-v${{ env.VERSION_NAME }}-standard.apk
           
-          # ARM64 APK
+          # F-Droid Flavor - Universal APK
-          cp android/app/build/outputs/apk/release/app-arm64-v8a-release.apk \
+          cp android/app/build/outputs/apk/fdroid/release/app-fdroid-release.apk \
-             apk-output/simple-notes-sync-v${{ env.VERSION_NAME }}-arm64-v8a.apk
+             apk-output/simple-notes-sync-v${{ env.VERSION_NAME }}-fdroid.apk
           
-          # ARMv7 APK
+          echo "✅ APK-Dateien vorbereitet:"
-          cp android/app/build/outputs/apk/release/app-armeabi-v7a-release.apk \
-             apk-output/simple-notes-sync-v${{ env.VERSION_NAME }}-armeabi-v7a.apk
-          
-          echo "✅ APK files prepared:"
           ls -lh apk-output/
       
-      - name: Upload APK artifacts
+      - name: APK-Artefakte hochladen
         uses: actions/upload-artifact@v4
         with:
           name: simple-notes-sync-apks-v${{ env.VERSION_NAME }}
           path: apk-output/*.apk
-          retention-days: 90  # Keep production builds longer
+          retention-days: 90  # Produktions-Builds länger aufbewahren
       
-      - name: Get commit info
+      - name: Commit-Informationen auslesen
         run: |
           echo "SHORT_SHA=$(git rev-parse --short HEAD)" >> $GITHUB_ENV
           echo "COMMIT_DATE=$(git log -1 --format=%cd --date=iso-strict)" >> $GITHUB_ENV
+      
+      - name: F-Droid Changelogs lesen
+        run: |
+          # Lese deutsche Changelog (Hauptsprache) - Use printf to ensure proper formatting
+          if [ -f "fastlane/metadata/android/de-DE/changelogs/${{ env.BUILD_NUMBER }}.txt" ]; then
+            CHANGELOG_CONTENT=$(cat "fastlane/metadata/android/de-DE/changelogs/${{ env.BUILD_NUMBER }}.txt")
+            echo "CHANGELOG_DE<<GHADELIMITER" >> $GITHUB_ENV
+            echo "$CHANGELOG_CONTENT" >> $GITHUB_ENV
+            echo "GHADELIMITER" >> $GITHUB_ENV
+          else
+            echo "CHANGELOG_DE=Keine deutschen Release Notes verfügbar." >> $GITHUB_ENV
+          fi
           
-          # Get full commit message preserving newlines and emojis (UTF-8)
+          # Lese englische Changelog (optional)
-          {
+          if [ -f "fastlane/metadata/android/en-US/changelogs/${{ env.BUILD_NUMBER }}.txt" ]; then
-            echo 'COMMIT_MSG<<EOF'
+            CHANGELOG_CONTENT_EN=$(cat "fastlane/metadata/android/en-US/changelogs/${{ env.BUILD_NUMBER }}.txt")
-            git -c core.quotepath=false log -1 --pretty=%B
+            echo "CHANGELOG_EN<<GHADELIMITER" >> $GITHUB_ENV
-            echo 'EOF'
+            echo "$CHANGELOG_CONTENT_EN" >> $GITHUB_ENV
-          } >> $GITHUB_ENV
+            echo "GHADELIMITER" >> $GITHUB_ENV
+          else
+            echo "CHANGELOG_EN=" >> $GITHUB_ENV
+          fi
       
       - name: Create Production Release
         uses: softprops/action-gh-release@v1
         with:
           tag_name: ${{ env.VERSION_TAG }}
-          name: "📝 Simple Notes Sync v${{ env.VERSION_NAME }} (Produktions-Release)"
+          name: "📝 Simple Notes Sync v${{ env.VERSION_NAME }}"
           files: apk-output/*.apk
           draft: false
           prerelease: false
           generate_release_notes: false
           body: |
-            # 📝 Produktions-Release: Simple Notes Sync v${{ env.VERSION_NAME }}
+            ## 📦 Downloads
             
-            ## Build-Informationen
+            | Variante | Datei | Info |
+            |----------|-------|------|
+            | **🏆 Empfohlen** | `simple-notes-sync-v${{ env.VERSION_NAME }}-standard.apk` | Standard-Version (funktioniert auf allen Geraeten) |
+            | F-Droid | `simple-notes-sync-v${{ env.VERSION_NAME }}-fdroid.apk` | Fuer F-Droid Store |
             
-            - **Version:** ${{ env.VERSION_NAME }}+${{ env.BUILD_NUMBER }}
+            ---
-            - **Build-Datum:** ${{ env.COMMIT_DATE }}
+            
+            ## 📋 Changelog / Release Notes
+            
+            ${{ env.CHANGELOG_DE }}
+            
+            <details>
+            <summary>🌍 English Version</summary>
+            
+            ${{ env.CHANGELOG_EN }}
+            
+            </details>
+            
+            ---
+            
+            ## 📊 Build-Info
+            
+            - **Version:** ${{ env.VERSION_NAME }} (Code: ${{ env.BUILD_NUMBER }})
+            - **Datum:** ${{ env.COMMIT_DATE }}
             - **Commit:** ${{ env.SHORT_SHA }}
-            - **Umgebung:** 🟢 **PRODUKTION**
             
             ---
             
-            ## 📋 Änderungen
+            **[📖 Dokumentation](https://github.com/inventory69/simple-notes-sync/blob/main/QUICKSTART.md)** · **[🐛 Issue melden](https://github.com/inventory69/simple-notes-sync/issues)**
-            
-            ${{ env.COMMIT_MSG }}
-            
-            ---
-            
-            ## 📦 Download & Installation
-            
-            ### Welche APK soll ich herunterladen?
-            
-            | Dein Gerät | Lade diese APK herunter | Größe | Kompatibilität |
-            |------------|------------------------|-------|----------------|
-            | 🤷 Nicht sicher? | `simple-notes-sync-v${{ env.VERSION_NAME }}-universal.apk` | ~5 MB | Funktioniert auf allen Geräten |
-            | Modern (2018+) | `simple-notes-sync-v${{ env.VERSION_NAME }}-arm64-v8a.apk` | ~3 MB | Schneller, kleiner |
-            | Ältere Geräte | `simple-notes-sync-v${{ env.VERSION_NAME }}-armeabi-v7a.apk` | ~3 MB | Ältere ARM-Chips |
-            
-            ### Installationsschritte
-            1. Lade die passende APK aus den Assets unten herunter
-            2. Aktiviere "Installation aus unbekannten Quellen" in den Android-Einstellungen
-            3. Öffne die heruntergeladene APK-Datei
-            4. Folge den Installationsanweisungen
-            5. Konfiguriere die WebDAV-Einstellungen in der App
-            
-            ---
-            
-            ## ⚙️ Funktionen
-            
-            - ✅ Automatische WebDAV-Synchronisation alle 30 Minuten (~0,4% Akku/Tag)
-            - ✅ Intelligente Gateway-Erkennung (automatische Heimnetzwerk-Erkennung)
-            - ✅ Material Design 3 Oberfläche
-            - ✅ Datenschutzorientiert (kein Tracking, keine Analysen)
-            - ✅ Offline-First Architektur
-            
-            ---
-            
-            ## 🔄 Update von vorheriger Version
-            
-            Installiere diese APK einfach über die bestehende Installation - alle Daten und Einstellungen bleiben erhalten.
-            
-            ---
-            
-            ## 📱 Obtanium - Auto-Update App
-            
-            Erhalte automatische Updates mit [Obtanium](https://github.com/ImranR98/Obtanium/releases/latest).
-            
-            **Einrichtung:**
-            1. Installiere Obtanium über den Link oben
-            2. Füge die App mit dieser URL hinzu: `https://github.com/dettmersLiq/simple-notes-sync`
-            3. Aktiviere Auto-Updates
-            
-            ---
-            
-            ## 🆘 Support
-            
-            Bei Problemen oder Fragen öffne bitte ein Issue auf GitHub.
-            
-            ---
-            
-            ## 🔒 Datenschutz & Sicherheit
-            
-            - Alle Daten werden über deinen eigenen WebDAV-Server synchronisiert
-            - Keine Drittanbieter-Analysen oder Tracking
-            - Keine Internet-Berechtigungen außer für WebDAV-Sync
-            - Alle Synchronisationsvorgänge verschlüsselt (HTTPS)
-            - Open Source - prüfe den Code selbst
-            
-            ---
-            
-            ## 🛠️ Erstellt mit
-            
-            - **Sprache:** Kotlin
-            - **UI:** Material Design 3
-            - **Sync:** WorkManager + WebDAV
-            - **Target SDK:** Android 16 (API 36)
-            - **Min SDK:** Android 8.0 (API 26)
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/pr-build-check.yml

@@ -0,0 +1,99 @@
+name: PR Build Check
+on:
+  pull_request:
+    branches: [ main ]
+    paths:
+      - 'android/**'
+      - '.github/workflows/pr-build-check.yml'
+jobs:
+  build:
+    name: Build & Test APK
+    runs-on: ubuntu-latest
+    steps:
+      - name: Code auschecken
+        uses: actions/checkout@v4
+      - name: Java einrichten
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '17'
+      - name: Gradle Cache
+        uses: actions/cache@v3
+        with:
+          path: |
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+          restore-keys: |
+            ${{ runner.os }}-gradle-
+      - name: Version auslesen
+        run: |
+          VERSION_NAME=$(grep "versionName = " android/app/build.gradle.kts | sed 's/.*versionName = "\(.*\)".*/\1/')
+          VERSION_CODE=$(grep "versionCode = " android/app/build.gradle.kts | sed 's/.*versionCode = \([0-9]*\).*/\1/')
+          echo "VERSION_NAME=$VERSION_NAME" >> $GITHUB_ENV
+          echo "VERSION_CODE=$VERSION_CODE" >> $GITHUB_ENV
+          echo "📱 Version: $VERSION_NAME (Code: $VERSION_CODE)"
+      - name: Debug Build erstellen (ohne Signing)
+        run: |
+          cd android
+          ./gradlew assembleStandardDebug assembleFdroidDebug --no-daemon --stacktrace
+      - name: Unit Tests ausfuehren
+        run: |
+          cd android
+          ./gradlew test --no-daemon --stacktrace
+        continue-on-error: true
+      - name: Build-Ergebnis pruefen
+        run: |
+          if [ -f "android/app/build/outputs/apk/standard/debug/app-standard-universal-debug.apk" ]; then
+            echo "✅ Standard Debug APK erfolgreich gebaut"
+            ls -lh android/app/build/outputs/apk/standard/debug/*.apk
+          else
+            echo "❌ Standard Debug APK Build fehlgeschlagen"
+            exit 1
+          fi
+          if [ -f "android/app/build/outputs/apk/fdroid/debug/app-fdroid-universal-debug.apk" ]; then
+            echo "✅ F-Droid Debug APK erfolgreich gebaut"
+            ls -lh android/app/build/outputs/apk/fdroid/debug/*.apk
+          else
+            echo "❌ F-Droid Debug APK Build fehlgeschlagen"
+            exit 1
+          fi
+      - name: Debug APKs hochladen (Artefakte)
+        uses: actions/upload-artifact@v4
+        with:
+          name: debug-apks-pr-${{ github.event.pull_request.number }}
+          path: |
+            android/app/build/outputs/apk/standard/debug/*.apk
+            android/app/build/outputs/apk/fdroid/debug/*.apk
+          retention-days: 30
+      - name: Kommentar zu PR hinzufuegen
+        uses: actions/github-script@v7
+        if: success()
+        with:
+          script: |
+            const fs = require('fs');
+            const standardApk = fs.readdirSync('android/app/build/outputs/apk/standard/debug/')
+              .filter(f => f.endsWith('.apk'));
+            const fdroidApk = fs.readdirSync('android/app/build/outputs/apk/fdroid/debug/')
+              .filter(f => f.endsWith('.apk'));
+            github.rest.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: `## ✅ Build erfolgreich!
+            
+            **Version:** ${{ env.VERSION_NAME }} (Code: ${{ env.VERSION_CODE }})
+            
+            ### 📦 Debug APKs (Test-Builds)
+            Die Debug-APKs wurden erfolgreich gebaut und sind als Artefakte verfuegbar:
+            
+            **Standard Flavor:**
+            ${standardApk.map(f => '- \`' + f + '\`').join('\n')}
+            
+            **F-Droid Flavor:**
+            ${fdroidApk.map(f => '- \`' + f + '\`').join('\n')}
+            
+            > ⚠️ **Hinweis:** Dies sind unsigned Debug-Builds zum Testen. Production Releases werden nur bei Merge auf \`main\` erstellt.
+            
+            [📥 Download Artefakte](https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }})`
+            })

CHANGELOG.md

@@ -0,0 +1,387 @@
+# Changelog
+
+All notable changes to Simple Notes Sync will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
+
+---
+
+## [1.3.2] - 2026-01-10
+
+### Changed
+- **🧹 Code-Qualität: "Clean Slate" Release**
+  - Alle einfachen Lint-Issues behoben (Phase 1-7 des Cleanup-Plans)
+  - Unused Imports und Members entfernt
+  - Magic Numbers durch benannte Konstanten ersetzt
+  - SwallowedExceptions mit Logger.w() versehen
+  - MaxLineLength-Verstöße reformatiert
+  - ConstructorParameterNaming (snake_case → camelCase mit @SerializedName)
+  - Custom Exceptions: SyncException.kt und ValidationException.kt erstellt
+
+### Added  
+- **📝 F-Droid Privacy Notice**
+  - Datenschutz-Hinweis für die Datei-Logging-Funktion
+  - Erklärt dass Logs nur lokal gespeichert werden
+  - Erfüllt F-Droid Opt-in Consent-Anforderungen
+
+### Technical Improvements
+- **⚡ Neue Konstanten für bessere Wartbarkeit**
+  - `SYNC_COMPLETED_DELAY_MS`, `ERROR_DISPLAY_DELAY_MS` (MainActivity)
+  - `CONNECTION_TIMEOUT_MS` (SettingsActivity)
+  - `SOCKET_TIMEOUT_MS`, `MAX_FILENAME_LENGTH`, `ETAG_PREVIEW_LENGTH` (WebDavSyncService)
+  - `AUTO_CANCEL_TIMEOUT_MS` (NotificationHelper)
+  - RFC 1918 IP-Range Konstanten (UrlValidator)
+  - `DAYS_THRESHOLD`, `TRUNCATE_SUFFIX_LENGTH` (Extensions)
+
+- **🔒 @Suppress Annotations für legitime Patterns**
+  - ReturnCount: Frühe Returns für Validierung sind idiomatisch
+  - LoopWithTooManyJumpStatements: Komplexe Sync-Logik dokumentiert
+
+### Notes
+- Komplexe Refactorings (LargeClass, LongMethod) für v1.3.3+ geplant
+- Deprecation-Warnungen (LocalBroadcastManager, ProgressDialog) bleiben bestehen
+
+---
+
+## [1.3.1] - 2026-01-08
+
+### Fixed
+- **🔧 Multi-Device JSON Sync (Danke an Thomas aus Bielefeld)**
+  - JSON-Dateien werden jetzt korrekt zwischen Geräten synchronisiert
+  - Funktioniert auch ohne aktiviertes Markdown
+  - Hybrid-Optimierung: Server-Timestamp (Primary) + E-Tag (Secondary) Checks
+  - E-Tag wird nach Upload gecached um Re-Download zu vermeiden
+
+### Performance Improvements
+- **⚡ JSON Sync Performance-Parität**
+  - JSON-Sync erreicht jetzt gleiche Performance wie Markdown (~2-3 Sekunden)
+  - Timestamp-basierte Skip-Logik für unveränderte Dateien (~500ms pro Datei gespart)
+  - E-Tag-Matching als Fallback für Dateien die seit letztem Sync modifiziert wurden
+  - **Beispiel:** 24 Dateien von 12-14s auf ~2.7s reduziert (keine Änderungen)
+
+- **⏭️ Skip unveränderte Dateien** (Haupt-Performance-Fix!)
+  - JSON-Dateien: Überspringt alle Notizen, die seit letztem Sync nicht geändert wurden
+  - Markdown-Dateien: Überspringt unveränderte MD-Dateien basierend auf Server-Timestamp
+  - **Spart ~500ms pro Datei** bei Nextcloud (~20 Dateien = 10 Sekunden gespart!)
+  - Von 21 Sekunden Sync-Zeit auf 2-3 Sekunden reduziert
+
+- **⚡ Session-Caching für WebDAV** 
+  - Sardine-Client wird pro Sync-Session wiederverwendet (~600ms gespart)
+  - WiFi-IP-Adresse wird gecacht statt bei jeder Anfrage neu ermittelt (~300ms gespart)
+  - `/notes/` Ordner-Existenz wird nur einmal pro Sync geprüft (~500ms gespart)
+  - **Gesamt: ~1.4 Sekunden zusätzlich gespart**
+
+- **📝 Content-basierte Markdown-Erkennung**
+  - Extern bearbeitete Markdown-Dateien werden auch erkannt wenn YAML-Timestamp nicht aktualisiert wurde
+  - Löst das Problem: Obsidian/Texteditor-Änderungen wurden nicht importiert
+  - Hybridansatz: Erst Timestamp-Check (schnell), dann Content-Vergleich (zuverlässig)
+
+### Added
+- **🔄 Sync-Status-Anzeige (UI)**
+  - Sichtbares Banner "Synchronisiere..." mit ProgressBar während Sync läuft
+  - Sync-Button und Pull-to-Refresh werden deaktiviert während Sync aktiv
+  - Verhindert versehentliche Doppel-Syncs durch visuelle Rückmeldung
+  - Auch in Einstellungen: "Jetzt synchronisieren" Button wird deaktiviert
+
+### Fixed
+- **🔧 Sync-Mutex verhindert doppelte Syncs**
+  - Keine doppelten Toast-Nachrichten mehr bei schnellem Pull-to-Refresh
+  - Concurrent Sync-Requests werden korrekt blockiert
+
+- **🐛 Lint-Fehler behoben**
+  - `View.generateViewId()` statt hardcodierte IDs in RadioButtons
+  - `app:tint` statt `android:tint` für AppCompat-Kompatibilität
+
+### Added
+- **🔍 detekt Code-Analyse**
+  - Statische Code-Analyse mit detekt 1.23.4 integriert
+  - Pragmatische Konfiguration für Sync-intensive Codebasis
+  - 91 Issues identifiziert (als Baseline für v1.4.0)
+
+- **🏗️ Debug Build mit separatem Package**
+  - Debug-APK kann parallel zur Release-Version installiert werden
+  - Package: `dev.dettmer.simplenotes.debug` (Debug) vs `dev.dettmer.simplenotes` (Release)
+  - App-Name zeigt "Simple Notes (Debug)" für einfache Unterscheidung
+
+- **📊 Debug-Logging UI**
+  - Neuer "Debug Log" Button in Einstellungen → Erweitert
+  - Zeigt letzte Sync-Logs mit Zeitstempeln
+  - Export-Funktion für Fehlerberichte
+
+### Technical
+- `WebDavSyncService`: Hybrid-Optimierung für JSON-Downloads (Timestamp PRIMARY, E-Tag SECONDARY)
+- `WebDavSyncService`: E-Tag refresh nach Upload statt Invalidierung (verhindert Re-Download)
+- E-Tag Caching: `SharedPreferences` mit Key-Pattern `etag_json_{noteId}`
+- Skip-Logik: `if (serverModified <= lastSync) skip` → ~1ms pro Datei
+- Fallback E-Tag: `if (serverETag == cachedETag) skip` → für Dateien modifiziert nach lastSync
+- PROPFIND nach PUT: Fetch E-Tag nach Upload für korrektes Caching
+- `SyncStateManager`: Neuer Singleton mit `StateFlow<Boolean>` für Sync-Status
+- `MainActivity`: Observer auf `SyncStateManager.isSyncing` für UI-Updates
+- Layout: `sync_status_banner` mit `ProgressBar` + `TextView`
+- `WebDavSyncService`: Skip-Logik für unveränderte JSON/MD Dateien basierend auf `lastSyncTimestamp`
+- `WebDavSyncService`: Neue Session-Cache-Variablen (`sessionSardine`, `sessionWifiAddress`, `notesDirEnsured`)
+- `getOrCreateSardine()`: Cached Sardine-Client mit automatischer Credentials-Konfiguration
+- `getOrCacheWiFiAddress()`: WiFi-Adresse wird nur einmal pro Sync ermittelt
+- `clearSessionCache()`: Aufräumen am Ende jeder Sync-Session
+- `ensureNotesDirectoryExists()`: Cached Directory-Check
+- Content-basierter Import: Vergleicht MD-Content mit lokaler Note wenn Timestamps gleich
+- Build-Tooling: detekt aktiviert, ktlint vorbereitet (deaktiviert wegen Parser-Problemen)
+- Debug BuildType: `applicationIdSuffix = ".debug"`, `versionNameSuffix = "-debug"`
+
+---
+
+## [1.3.0] - 2026-01-07
+
+### Added
+- **🚀 Multi-Device Sync** (Thanks to Thomas from Bielefeld for reporting!)
+  - Automatic download of new notes from other devices
+  - Deletion tracking prevents "zombie notes" (deleted notes don't come back)
+  - Smart cleanup: Re-created notes (newer timestamp) are downloaded
+  - Works with all devices: v1.2.0, v1.2.1, v1.2.2, and v1.3.0
+
+- **🗑️ Server Deletion via Swipe Gesture**
+  - Swipe left on notes to delete from server (requires confirmation)
+  - Prevents duplicate notes on other devices
+  - Works with deletion tracking system
+  - Material Design confirmation dialog
+
+- **⚡ E-Tag Performance Optimization**
+  - Smart server checking with E-Tag caching (~150ms vs 3000ms for "no changes")
+  - 20x faster when server has no updates
+  - E-Tag hybrid approach: E-Tag for JSON (fast), timestamp for Markdown (reliable)
+  - Battery-friendly with minimal server requests
+
+- **📥 Markdown Auto-Sync Toggle**
+  - NEW: Unified Auto-Sync toggle in Settings (replaces separate Export/Auto-Import toggles)
+  - When enabled: Notes export to Markdown AND import changes automatically
+  - When disabled: Manual sync button appears for on-demand synchronization
+  - Performance: Auto-Sync OFF = 0ms overhead
+
+- **🔘 Manual Markdown Sync Button**
+  - Manual sync button for performance-conscious users
+  - Shows import/export counts after completion
+  - Only visible when Auto-Sync is disabled
+  - On-demand synchronization (~150-200ms only when triggered)
+
+- **⚙️ Server-Restore Modes**
+  - MERGE: Keep local notes + add server notes
+  - REPLACE: Delete all local + download from server
+  - OVERWRITE: Update duplicates, keep non-duplicates
+  - Restore modes now work correctly for WebDAV restore
+
+### Technical
+- New `DeletionTracker` model with JSON persistence
+- `NotesStorage`: Added deletion tracking methods
+- `WebDavSyncService.hasUnsyncedChanges()`: Intelligent server checks with E-Tag caching
+- `WebDavSyncService.downloadRemoteNotes()`: Deletion-aware downloads
+- `WebDavSyncService.restoreFromServer()`: Support for restore modes
+- `WebDavSyncService.deleteNoteFromServer()`: Server deletion with YAML frontmatter scanning
+- `WebDavSyncService.importMarkdownFiles()`: Automatic Markdown import during sync
+- `WebDavSyncService.manualMarkdownSync()`: Manual sync with result counts
+- `MainActivity.setupSwipeToDelete()`: Two-stage swipe deletion with confirmation
+- E-Tag caching in SharedPreferences for performance
+
+---
+
+## [1.2.2] - 2026-01-06
+
+### Fixed
+- **Backward Compatibility for v1.2.0 Users (Critical)**
+  - App now reads BOTH old (Root) AND new (`/notes/`) folder structures
+  - Users upgrading from v1.2.0 no longer lose their existing notes
+  - Server-Restore now finds notes from v1.2.0 stored in Root folder
+  - Automatic deduplication prevents loading the same note twice
+  - Graceful error handling if Root folder is not accessible
+
+### Technical
+- `WebDavSyncService.downloadRemoteNotes()` - Dual-mode download (Root + /notes/)
+- `WebDavSyncService.restoreFromServer()` - Now uses dual-mode download
+- Migration happens naturally: new uploads go to `/notes/`, old notes stay readable
+
+---
+
+## [1.2.1] - 2026-01-05
+
+### Fixed
+- **Markdown Initial Export Bugfix**
+  - Existing notes are now exported as Markdown when Desktop Integration is activated
+  - Previously, only new notes created after activation were exported
+  - Progress dialog shows export status with current/total counter
+  - Error handling for network issues during export
+  - Individual note failures don't abort the entire export
+
+- **Markdown Directory Structure Fix**
+  - Markdown files now correctly land in `/notes-md/` folder
+  - Smart URL detection supports both Root-URL and `/notes` URL structures
+  - Previously, MD files were incorrectly placed in the root directory
+  - Markdown import now finds files correctly
+
+- **JSON URL Normalization**
+  - Simplified server configuration: enter only base URL (e.g., `http://server:8080/`)
+  - App automatically creates `/notes/` for JSON files and `/notes-md/` for Markdown
+  - Smart detection: both `http://server:8080/` and `http://server:8080/notes/` work correctly
+  - Backward compatible: existing setups with `/notes` in URL continue to work
+  - No migration required for existing users
+
+### Changed
+- **Markdown Directory Creation**
+  - `notes-md/` folder is now created on first sync (regardless of Desktop Integration setting)
+  - Prevents 404 errors when mounting WebDAV folder
+  - Better user experience: folder is visible before enabling the feature
+
+- **Settings UI Improvements**
+  - Updated example URL from `/webdav` to `/notes` to match app behavior
+  - Example now shows: `http://192.168.0.188:8080/notes`
+
+### Technical
+- `WebDavSyncService.ensureMarkdownDirectoryExists()` - Creates MD folder early
+- `WebDavSyncService.getMarkdownUrl()` - Smart URL detection for both structures
+- `WebDavSyncService.exportAllNotesToMarkdown()` - Exports all local notes with progress callback
+- `SettingsActivity.onMarkdownExportToggled()` - Triggers initial export with ProgressDialog
+
+---
+
+## [1.2.0] - 2026-01-04
+
+### Added
+- **Local Backup System**
+  - Export all notes as JSON file to any location (Downloads, SD card, cloud folder)
+  - Import backup with 3 modes: Merge, Replace, or Overwrite duplicates
+  - Automatic safety backup created before every restore
+  - Backup validation (format and version check)
+  
+- **Markdown Desktop Integration**
+  - Optional Markdown export parallel to JSON sync
+  - `.md` files synced to `notes-md/` folder on WebDAV
+  - YAML frontmatter with `id`, `created`, `updated`, `device`
+  - Manual import button to pull Markdown changes from server
+  - Last-Write-Wins conflict resolution via timestamps
+  
+- **Settings UI Extensions**
+  - New "Backup & Restore" section with local + server restore
+  - New "Desktop Integration" section with Markdown toggle
+  - Universal restore dialog with radio button mode selection
+
+### Changed
+- **Server Restore Behavior**: Users now choose restore mode (Merge/Replace/Overwrite) instead of hard-coded replace-all
+
+### Technical
+- `BackupManager.kt` - Complete backup/restore logic
+- `Note.toMarkdown()` / `Note.fromMarkdown()` - Markdown conversion with YAML frontmatter
+- `WebDavSyncService` - Extended for dual-format sync (JSON master + Markdown mirror)
+- ISO8601 timestamp formatting for desktop compatibility
+- Filename sanitization for safe Markdown file names
+
+### Documentation
+- Added WebDAV mount instructions (Windows, macOS, Linux)
+- Created [SYNC_ARCHITECTURE.md](../project-docs/simple-notes-sync/architecture/SYNC_ARCHITECTURE.md) - Complete sync documentation
+- Created [MARKDOWN_DESKTOP_REALITY_CHECK.md](../project-docs/simple-notes-sync/markdown-desktop-plan/MARKDOWN_DESKTOP_REALITY_CHECK.md) - Desktop integration analysis
+
+---
+
+## [1.1.2] - 2025-12-28
+
+### Fixed
+- **"Job was cancelled" Error**
+  - Fixed coroutine cancellation in sync worker
+  - Proper error handling for interrupted syncs
+  
+- **UI Improvements**
+  - Back arrow instead of X in note editor (better UX)
+  - Pull-to-refresh for manual sync trigger
+  - HTTP/HTTPS protocol selection with radio buttons
+  - Inline error display (no toast spam)
+  
+- **Performance & Battery**
+  - Sync only on actual changes (saves battery)
+  - Auto-save notifications removed
+  - 24-hour server offline warning instead of instant error
+  
+### Changed
+- Settings grouped into "Auto-Sync" and "Sync Interval" sections
+- HTTP only allowed for local networks (RFC 1918 IPs)
+- Swipe-to-delete without UI flicker
+
+---
+
+## [1.1.1] - 2025-12-27
+
+### Fixed
+- **WiFi Connect Sync**
+  - No error notifications in foreign WiFi networks
+  - Server reachability check before sync (2s timeout)
+  - Silent abort when server offline
+  - Pre-check waits until network is ready
+  - No errors during network initialization
+  
+### Changed
+- **Notifications**
+  - Old sync notifications cleared on app start
+  - Error notifications auto-dismiss after 30 seconds
+  
+### UI
+- Sync icon only shown when sync is configured
+- Swipe-to-delete without flicker
+- Scroll to top after saving note
+
+### Technical
+- Server check with 2-second timeout before sync attempts
+- Network readiness check in WiFi connect trigger
+- Notification cleanup on MainActivity.onCreate()
+
+---
+
+## [1.1.0] - 2025-12-26
+
+### Added
+- **Configurable Sync Intervals**
+  - User choice: 15, 30, or 60 minutes
+  - Real-world battery impact displayed (15min: ~0.8%/day, 30min: ~0.4%/day, 60min: ~0.2%/day)
+  - Radio button selection in settings
+  - Doze Mode optimization (syncs batched in maintenance windows)
+  
+- **About Section**
+  - App version from BuildConfig
+  - Links to GitHub repository and developer profile
+  - MIT license information
+  - Material 3 card design
+
+### Changed
+- Settings UI redesigned with grouped sections
+- Periodic sync updated dynamically when interval changes
+- WorkManager uses selected interval for background sync
+
+### Removed
+- Debug/Logs section from settings (cleaner UI)
+
+### Technical
+- `PREF_SYNC_INTERVAL_MINUTES` preference key
+- NetworkMonitor reads interval from SharedPreferences
+- `ExistingPeriodicWorkPolicy.UPDATE` for live interval changes
+
+---
+
+## [1.0.0] - 2025-12-25
+
+### Added
+- Initial release
+- WebDAV synchronization
+- Note creation, editing, deletion
+- 6 sync triggers:
+  - Periodic sync (configurable interval)
+  - App start sync
+  - WiFi connect sync
+  - Manual sync (menu button)
+  - Pull-to-refresh
+  - Settings "Sync Now" button
+- Material 3 design
+- Light/Dark theme support
+- F-Droid compatible (100% FOSS)
+
+---
+
+[1.2.0]: https://github.com/inventory69/simple-notes-sync/releases/tag/v1.2.0
+[1.1.2]: https://github.com/inventory69/simple-notes-sync/releases/tag/v1.1.2
+[1.1.1]: https://github.com/inventory69/simple-notes-sync/releases/tag/v1.1.1
+[1.1.0]: https://github.com/inventory69/simple-notes-sync/releases/tag/v1.1.0
+[1.0.0]: https://github.com/inventory69/simple-notes-sync/releases/tag/v1.0.0

CONTRIBUTING.md

@@ -0,0 +1,263 @@
+# Contributing to Simple Notes Sync 🤝
+
+> Beiträge sind willkommen! / Contributions are welcome!
+
+**🌍 Languages:** [Deutsch](#deutsch) · [English](#english)
+
+---
+
+## Deutsch
+
+Danke, dass du zu Simple Notes Sync beitragen möchtest! 
+
+### 🚀 Schnellstart
+
+1. **Fork & Clone**
+   ```bash
+   git clone https://github.com/DEIN-USERNAME/simple-notes-sync.git
+   cd simple-notes-sync
+   ```
+
+2. **Branch erstellen**
+   ```bash
+   git checkout -b feature/mein-feature
+   # oder
+   git checkout -b fix/mein-bugfix
+   ```
+
+3. **Änderungen machen**
+   - Code schreiben
+   - Testen
+   - Committen mit aussagekräftiger Message
+
+4. **Pull Request erstellen**
+   - Push deinen Branch: `git push origin feature/mein-feature`
+   - Gehe zu GitHub und erstelle einen Pull Request
+   - Beschreibe deine Änderungen
+
+### 🧪 Automatische Tests
+
+Wenn du einen Pull Request erstellst, läuft automatisch ein **Build Check**:
+
+- ✅ Debug APKs werden gebaut (Standard + F-Droid)
+- ✅ Unit Tests werden ausgeführt
+- ✅ APKs werden als Artefakte hochgeladen (zum Testen)
+- ✅ Build-Status wird als Kommentar im PR gepostet
+
+**Wichtig:** Der Build muss erfolgreich sein (grüner Haken ✅) bevor der PR gemerged werden kann.
+
+### 📱 Android App Development
+
+**Build lokal testen:**
+```bash
+cd android
+
+# Debug Build
+./gradlew assembleStandardDebug
+
+# Tests ausführen
+./gradlew test
+
+# Lint Check
+./gradlew lint
+```
+
+**Anforderungen:**
+- Android SDK 36 (Target)
+- Android SDK 24 (Minimum)
+- JDK 17
+- Kotlin 1.9+
+
+### 📝 Code Style
+
+- **Kotlin:** Folge den [Kotlin Coding Conventions](https://kotlinlang.org/docs/coding-conventions.html)
+- **Formatierung:** Android Studio Default Formatter
+- **Kommentare:** Deutsch oder Englisch (bevorzugt Englisch für Code)
+
+### 🐛 Bug Reports
+
+Nutze die [Bug Report Template](https://github.com/inventory69/simple-notes-sync/issues/new/choose) mit:
+- Android Version
+- App Version
+- Schritte zum Reproduzieren
+- Erwartetes vs. tatsächliches Verhalten
+
+### 💡 Feature Requests
+
+Nutze die [Feature Request Template](https://github.com/inventory69/simple-notes-sync/issues/new/choose) und beschreibe:
+- Was soll hinzugefügt werden
+- Warum ist es nützlich
+- Wie könnte es funktionieren
+
+### 📚 Dokumentation
+
+Dokumentations-Verbesserungen sind auch Contributions! 
+
+**Dateien:**
+- `README.md` / `README.en.md` - Übersicht
+- `QUICKSTART.md` / `QUICKSTART.en.md` - Schritt-für-Schritt Anleitung
+- `DOCS.md` / `DOCS.en.md` - Technische Details
+- `server/README.md` / `server/README.en.md` - Server Setup
+
+**Bitte:** Halte beide Sprachen (DE/EN) synchron!
+
+### ✅ Pull Request Checklist
+
+- [ ] Code kompiliert lokal (`./gradlew assembleStandardDebug`)
+- [ ] Tests laufen durch (`./gradlew test`)
+- [ ] Keine neuen Lint-Warnungen
+- [ ] Commit-Messages sind aussagekräftig
+- [ ] Dokumentation aktualisiert (falls nötig)
+- [ ] Beide Sprachen aktualisiert (bei Doku-Änderungen)
+
+### 🎯 Was wird akzeptiert?
+
+**✅ Gerne:**
+- Bug Fixes
+- Performance-Verbesserungen
+- Neue Features (nach Diskussion in einem Issue)
+- Dokumentations-Verbesserungen
+- Tests
+- UI/UX Verbesserungen
+
+**❌ Schwierig:**
+- Breaking Changes (bitte erst als Issue diskutieren)
+- Komplett neue Architektur
+- Dependencies mit fragwürdigen Lizenzen
+
+### 📄 Lizenz
+
+Indem du contributest, stimmst du zu dass dein Code unter der [MIT License](LICENSE) veröffentlicht wird.
+
+---
+
+## English
+
+Thanks for wanting to contribute to Simple Notes Sync!
+
+### 🚀 Quick Start
+
+1. **Fork & Clone**
+   ```bash
+   git clone https://github.com/YOUR-USERNAME/simple-notes-sync.git
+   cd simple-notes-sync
+   ```
+
+2. **Create Branch**
+   ```bash
+   git checkout -b feature/my-feature
+   # or
+   git checkout -b fix/my-bugfix
+   ```
+
+3. **Make Changes**
+   - Write code
+   - Test
+   - Commit with meaningful message
+
+4. **Create Pull Request**
+   - Push your branch: `git push origin feature/my-feature`
+   - Go to GitHub and create a Pull Request
+   - Describe your changes
+
+### 🧪 Automated Tests
+
+When you create a Pull Request, an automatic **Build Check** runs:
+
+- ✅ Debug APKs are built (Standard + F-Droid)
+- ✅ Unit tests are executed
+- ✅ APKs are uploaded as artifacts (for testing)
+- ✅ Build status is posted as comment in PR
+
+**Important:** The build must succeed (green checkmark ✅) before the PR can be merged.
+
+### 📱 Android App Development
+
+**Test build locally:**
+```bash
+cd android
+
+# Debug Build
+./gradlew assembleStandardDebug
+
+# Run tests
+./gradlew test
+
+# Lint Check
+./gradlew lint
+```
+
+**Requirements:**
+- Android SDK 36 (Target)
+- Android SDK 24 (Minimum)
+- JDK 17
+- Kotlin 1.9+
+
+### 📝 Code Style
+
+- **Kotlin:** Follow [Kotlin Coding Conventions](https://kotlinlang.org/docs/coding-conventions.html)
+- **Formatting:** Android Studio Default Formatter
+- **Comments:** German or English (preferably English for code)
+
+### 🐛 Bug Reports
+
+Use the [Bug Report Template](https://github.com/inventory69/simple-notes-sync/issues/new/choose) with:
+- Android version
+- App version
+- Steps to reproduce
+- Expected vs. actual behavior
+
+### 💡 Feature Requests
+
+Use the [Feature Request Template](https://github.com/inventory69/simple-notes-sync/issues/new/choose) and describe:
+- What should be added
+- Why is it useful
+- How could it work
+
+### 📚 Documentation
+
+Documentation improvements are also contributions!
+
+**Files:**
+- `README.md` / `README.en.md` - Overview
+- `QUICKSTART.md` / `QUICKSTART.en.md` - Step-by-step guide
+- `DOCS.md` / `DOCS.en.md` - Technical details
+- `server/README.md` / `server/README.en.md` - Server setup
+
+**Please:** Keep both languages (DE/EN) in sync!
+
+### ✅ Pull Request Checklist
+
+- [ ] Code compiles locally (`./gradlew assembleStandardDebug`)
+- [ ] Tests pass (`./gradlew test`)
+- [ ] No new lint warnings
+- [ ] Commit messages are meaningful
+- [ ] Documentation updated (if needed)
+- [ ] Both languages updated (for doc changes)
+
+### 🎯 What Gets Accepted?
+
+**✅ Welcome:**
+- Bug fixes
+- Performance improvements
+- New features (after discussion in an issue)
+- Documentation improvements
+- Tests
+- UI/UX improvements
+
+**❌ Difficult:**
+- Breaking changes (please discuss in issue first)
+- Completely new architecture
+- Dependencies with questionable licenses
+
+### 📄 License
+
+By contributing, you agree that your code will be published under the [MIT License](LICENSE).
+
+---
+
+## 🆘 Fragen? / Questions?
+
+Öffne ein [Issue](https://github.com/inventory69/simple-notes-sync/issues) oder nutze die [Question Template](https://github.com/inventory69/simple-notes-sync/issues/new/choose).
+
+**Frohe Weihnachten & Happy Coding! 🎄**

GITHUB_ACTIONS_SETUP.md

@@ -1,188 +0,0 @@
-# GitHub Actions Setup Guide
-
-This guide explains how to set up the GitHub Actions workflow for automated APK builds with proper signing.
-
-## Overview
-
-The workflow in `.github/workflows/build-production-apk.yml` automatically:
-- Builds signed APKs on every push to `main`
-- Generates version numbers using `YYYY.MM.DD` + build number
-- Creates 3 APK variants (universal, arm64-v8a, armeabi-v7a)
-- Creates GitHub releases with all APKs attached
-
-## Prerequisites
-
-- GitHub CLI (`gh`) installed
-- Java 17+ installed (for keytool)
-- Git repository initialized with GitHub remote
-
-## Step 1: Generate Signing Keystore
-
-⚠️ **IMPORTANT**: Store the keystore securely! Without it, you cannot publish updates to your app.
-
-```bash
-# Navigate to project root
-cd /path/to/simple-notes-sync
-
-# Generate keystore (replace values as needed)
-keytool -genkey -v \
-  -keystore android/app/simple-notes-release.jks \
-  -keyalg RSA \
-  -keysize 2048 \
-  -validity 10000 \
-  -alias simple-notes
-
-# You will be prompted for:
-# - Keystore password (remember this!)
-# - Key password (remember this!)
-# - Your name, organization, etc.
-```
-
-**Store these securely:**
-- Keystore password
-- Key password
-- Alias: `simple-notes`
-- Keystore file: `android/app/simple-notes-release.jks`
-
-⚠️ **BACKUP**: Make a backup of the keystore file in a secure location (NOT in the repository).
-
-## Step 2: Base64 Encode Keystore
-
-```bash
-# Create base64 encoded version
-base64 android/app/simple-notes-release.jks > simple-notes-release.jks.b64
-
-# Or on macOS:
-base64 -i android/app/simple-notes-release.jks -o simple-notes-release.jks.b64
-```
-
-## Step 3: Set GitHub Secrets
-
-Using GitHub CLI (recommended):
-
-```bash
-# Set KEYSTORE_BASE64 secret
-gh secret set KEYSTORE_BASE64 < simple-notes-release.jks.b64
-
-# Set KEYSTORE_PASSWORD (will prompt for input)
-gh secret set KEYSTORE_PASSWORD
-
-# Set KEY_PASSWORD (will prompt for input)
-gh secret set KEY_PASSWORD
-
-# Set KEY_ALIAS (value: simple-notes)
-printf "simple-notes" | gh secret set KEY_ALIAS
-```
-
-Or manually via GitHub web interface:
-1. Go to repository Settings → Secrets and variables → Actions
-2. Click "New repository secret"
-3. Add these secrets:
-   - `KEYSTORE_BASE64`: Paste content of `simple-notes-release.jks.b64`
-   - `KEYSTORE_PASSWORD`: Your keystore password
-   - `KEY_PASSWORD`: Your key password
-   - `KEY_ALIAS`: `simple-notes`
-
-## Step 4: Verify Setup
-
-```bash
-# Check secrets are set
-gh secret list
-
-# Expected output:
-# KEYSTORE_BASE64  Updated YYYY-MM-DD
-# KEYSTORE_PASSWORD  Updated YYYY-MM-DD
-# KEY_PASSWORD  Updated YYYY-MM-DD
-# KEY_ALIAS  Updated YYYY-MM-DD
-```
-
-## Step 5: Cleanup
-
-```bash
-# Remove sensitive files (they're in .gitignore, but double-check)
-rm simple-notes-release.jks.b64
-rm -f android/key.properties  # Generated by workflow
-
-# Verify keystore is NOT tracked by git
-git status | grep -i jks
-# Should return nothing
-```
-
-## Step 6: Trigger First Build
-
-```bash
-# Commit and push to main
-git add .
-git commit -m "🚀 feat: Add GitHub Actions deployment workflow"
-git push origin main
-
-# Or manually trigger workflow
-gh workflow run build-production-apk.yml
-```
-
-## Verification
-
-1. Go to GitHub repository → Actions tab
-2. Check workflow run status
-3. Once complete, go to Releases tab
-4. Verify release was created with 3 APK variants
-5. Download and test one of the APKs
-
-## Troubleshooting
-
-### Build fails with "Keystore not found"
-- Check `KEYSTORE_BASE64` secret is set correctly
-- Verify base64 encoding was done without line breaks
-
-### Build fails with "Incorrect password"
-- Verify `KEYSTORE_PASSWORD` and `KEY_PASSWORD` are correct
-- Re-set secrets if needed
-
-### APK files not found
-- Check build logs for errors in assembleRelease step
-- Verify APK output paths match workflow expectations
-
-### Updates don't work
-- Ensure you're using the same keystore for all builds
-- Verify `applicationId` in build.gradle.kts matches
-
-## Security Notes
-
-- ✅ Keystore is base64-encoded in GitHub secrets (secure)
-- ✅ Passwords are stored in GitHub secrets (encrypted)
-- ✅ `key.properties` and `.jks` files are in `.gitignore`
-- ⚠️ Never commit keystore files to repository
-- ⚠️ Keep backup of keystore in secure location
-- ⚠️ Don't share keystore passwords
-
-## Versioning
-
-Versions follow this pattern:
-- **Version Name**: `YYYY.MM.DD` (e.g., `2025.01.15`)
-- **Version Code**: GitHub run number (e.g., `42`)
-- **Release Tag**: `vYYYY.MM.DD-prod.BUILD` (e.g., `v2025.01.15-prod.42`)
-
-This ensures:
-- Semantic versioning based on release date
-- Incremental version codes for Play Store compatibility
-- Clear distinction between builds
-
-## APK Variants
-
-The workflow generates 3 APK variants:
-
-1. **Universal APK** (~5 MB)
-   - Works on all devices
-   - Larger file size
-   - Recommended for most users
-
-2. **arm64-v8a APK** (~3 MB)
-   - For modern devices (2018+)
-   - Smaller, faster
-   - 64-bit ARM processors
-
-3. **armeabi-v7a APK** (~3 MB)
-   - For older devices
-   - 32-bit ARM processors
-
-Users can choose based on their device - Obtanium auto-updates work with all variants.

QUICKSTART.en.md

@@ -0,0 +1,271 @@
+# Quick Start Guide - Simple Notes Sync 📝
+
+> Step-by-step installation and setup guide
+
+**🌍 Languages:** [Deutsch](QUICKSTART.md) · **English**
+
+---
+
+## Prerequisites
+
+- ✅ Android 8.0+ smartphone/tablet
+- ✅ WiFi connection
+- ✅ Own server with Docker (optional - for self-hosting)
+
+---
+
+## Option 1: With own server (Self-Hosted) 🏠
+
+### Step 1: Setup WebDAV Server
+
+On your server (e.g. Raspberry Pi, NAS, VPS):
+
+```bash
+# Clone repository
+git clone https://github.com/inventory69/simple-notes-sync.git
+cd simple-notes-sync/server
+
+# Configure environment variables
+cp .env.example .env
+nano .env
+```
+
+**Adjust in `.env`:**
+```env
+WEBDAV_PASSWORD=your-secure-password-here
+```
+
+**Start server:**
+```bash
+docker compose up -d
+```
+
+**Find IP address:**
+```bash
+ip addr show | grep "inet " | grep -v 127.0.0.1
+```
+
+➡️ **Note down:** `http://YOUR-SERVER-IP:8080/`
+
+---
+
+### Step 2: Install App
+
+1. **Download APK:** [Latest version](https://github.com/inventory69/simple-notes-sync/releases/latest)
+   - Choose: `simple-notes-sync-vX.X.X-standard-universal.apk`
+   
+2. **Allow installation:**
+   - Android: Settings → Security → Enable "Unknown sources" for your browser
+   
+3. **Open and install APK**
+
+---
+
+### Step 3: Configure App
+
+1. **Open app**
+
+2. **Open settings** (⚙️ icon top right)
+
+3. **Configure server settings:**
+   
+   | Field | Value |
+   |------|------|
+   | **WebDAV Server URL** | `http://YOUR-SERVER-IP:8080/` |
+   | **Username** | `noteuser` |
+   | **Password** | (your password from `.env`) |
+   | **Gateway SSID** | Name of your WiFi network |
+
+   > **💡 Note:** Enter only the base URL (without `/notes`). The app automatically creates `/notes/` for JSON files and `/notes-md/` for Markdown export.
+
+4. **Press "Test connection"****
+   - ✅ Success? → Continue to step 4
+   - ❌ Error? → See [Troubleshooting](#troubleshooting)
+
+5. **Enable auto-sync** (toggle switch)
+
+6. **Choose sync interval:**
+   - **15 min** - Maximum currency (~0.8% battery/day)
+   - **30 min** - Recommended (~0.4% battery/day) ⭐
+   - **60 min** - Maximum battery life (~0.2% battery/day)
+
+---
+
+### Step 4: Create First Note
+
+1. Back to main view (← arrow)
+
+2. **"Add note"** (+ icon)
+
+3. Enter title and text
+
+4. **Save** (💾 icon)
+
+5. **Wait for auto-sync** (or manually: ⚙️ → "Sync now")
+
+🎉 **Done!** Your notes will be automatically synchronized!
+
+---
+
+## Option 2: Local notes only (no server) 📱
+
+You can also use Simple Notes **without a server**:
+
+1. **Install app** (see step 2 above)
+
+2. **Use without server configuration:**
+   - Notes are only stored locally
+   - No auto-sync
+   - Perfect for offline-only use
+
+---
+
+## 🔋 Disable Battery Optimization
+
+For reliable auto-sync:
+
+1. **Settings** → **Apps** → **Simple Notes Sync**
+
+2. **Battery** → **Battery usage**
+
+3. Select: **"Don't optimize"** or **"Unrestricted"**
+
+💡 **Note:** Android Doze Mode may still delay sync in standby (~60 min). This is normal and affects all apps.
+
+---
+
+## 📊 Sync Intervals in Detail
+
+| Interval | Syncs/day | Battery/day | Battery/sync | Use case |
+|-----------|-----------|----------|-----------|----------------|
+| **15 min** | ~96 | ~0.8% (~23 mAh) | ~0.008% | ⚡ Maximum currency (multiple devices) |
+| **30 min** | ~48 | ~0.4% (~12 mAh) | ~0.008% | ✓ **Recommended** - balanced |
+| **60 min** | ~24 | ~0.2% (~6 mAh) | ~0.008% | 🔋 Maximum battery life |
+
+---
+
+## 🐛 Troubleshooting
+
+### Connection test fails
+
+**Problem:** "Connection failed" during test
+
+**Solutions:**
+
+1. **Server running?**
+   ```bash
+   docker compose ps
+   # Should show "Up"
+   ```
+
+2. **Same WiFi?**
+   - Smartphone and server must be on same network
+   - Check SSID in app settings
+
+3. **IP address correct?**
+   ```bash
+   ip addr show | grep "inet "
+   # Check if IP in URL matches
+   ```
+
+4. **Firewall?**
+   ```bash
+   # Open port 8080 (if firewall active)
+   sudo ufw allow 8080/tcp
+   ```
+
+5. **Check server logs:**
+   ```bash
+   docker compose logs -f
+   ```
+
+---
+
+### Auto-sync not working
+
+**Problem:** Notes are not automatically synchronized
+
+**Solutions:**
+
+1. **Auto-sync enabled?**
+   - ⚙️ Settings → Toggle "Auto-sync" must be **ON**
+
+2. **Battery optimization disabled?**
+   - See [Disable Battery Optimization](#-disable-battery-optimization)
+
+3. **On correct WiFi?**
+   - Sync only works when SSID = Gateway SSID
+   - Check current SSID in Android settings
+
+4. **Test manually:**
+   - ⚙️ Settings → "Sync now"
+   - Works? → Auto-sync should work too
+
+---
+
+### Notes not showing up
+
+**Problem:** After installation, no notes visible even though they exist on server
+
+**Solution:**
+
+1. **Manually sync once:**
+   - ⚙️ Settings → "Sync now"
+
+2. **Check server data:**
+   ```bash
+   docker compose exec webdav ls -la /data/
+   # Should show .json files
+   ```
+
+---
+
+### Sync errors
+
+**Problem:** Error message during sync
+
+**Solutions:**
+
+1. **"401 Unauthorized"** → Wrong password
+   - Check password in app settings
+   - Compare with `.env` on server
+
+2. **"404 Not Found"** → Wrong URL
+   - Should end with `/` (e.g. `http://192.168.1.100:8080/`)
+
+3. **"Network error"** → No connection
+   - See [Connection test fails](#connection-test-fails)
+
+---
+
+## 📱 Updates
+
+### Automatic with Obtainium (recommended)
+
+1. **[Install Obtainium](https://github.com/ImranR98/Obtanium/releases/latest)**
+
+2. **Add app:**
+   - URL: `https://github.com/inventory69/simple-notes-sync`
+   - Enable auto-update
+
+3. **Done!** Obtainium notifies you of new versions
+
+### Manual
+
+1. Download new APK from [Releases](https://github.com/inventory69/simple-notes-sync/releases/latest)
+
+2. Install (overwrites old version)
+
+3. All data remains intact!
+
+---
+
+## 🆘 Further Help
+
+- **GitHub Issues:** [Report problem](https://github.com/inventory69/simple-notes-sync/issues)
+- **Complete docs:** [DOCS.en.md](DOCS.en.md)
+- **Server setup details:** [server/README.en.md](server/README.en.md)
+
+---
+
+**Version:** 1.1.0 · **Created:** December 2025

QUICKSTART.md

@@ -1,208 +1,271 @@
-# 🚀 Quick Start Guide
+# Quick Start Guide - Simple Notes Sync 📝
 
-## ✅ Server ist bereits gestartet!
+> Schritt-für-Schritt Anleitung zur Installation und Einrichtung
 
-Der WebDAV-Server läuft bereits auf:
+**🌍 Sprachen:** **Deutsch** · [English](QUICKSTART.en.md)
-- **Lokal:** `http://localhost:8080/`
-- **Im Netzwerk:** `http://192.168.0.188:8080/`
-
-### Credentials
-- **Username:** `noteuser`
-- **Password:** `SimpleNotes2025!`
-
-## 📱 Nächste Schritte: Android App erstellen
-
-### Option 1: Mit Android Studio (Empfohlen)
-
-1. **Android Studio öffnen**
-   ```
-   File → New → New Project
-   ```
-
-2. **Template wählen:**
-   - Empty Views Activity
-
-3. **Projekt konfigurieren:**
-   ```
-   Name: Simple Notes
-   Package: com.example.simplenotes
-   Save location: /home/liq/gitProjects/simple-notes-sync/android/
-   Language: Kotlin
-   Minimum SDK: API 24 (Android 7.0)
-   Build configuration: Kotlin DSL
-   ```
-
-4. **Dependencies hinzufügen:**
-   
-   Öffne `app/build.gradle.kts` und füge hinzu:
-   ```kotlin
-   dependencies {
-       // ... existing dependencies
-       
-       // WebDAV
-       implementation("com.github.thegrizzlylabs:sardine-android:0.8")
-       
-       // Coroutines
-       implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.7.3")
-       
-       // JSON
-       implementation("com.google.code.gson:gson:2.10.1")
-       
-       // WorkManager
-       implementation("androidx.work:work-runtime-ktx:2.9.0")
-   }
-   ```
-   
-   Und in `settings.gradle.kts`:
-   ```kotlin
-   dependencyResolutionManagement {
-       repositories {
-           google()
-           mavenCentral()
-           maven { url = uri("https://jitpack.io") }  // Für Sardine
-       }
-   }
-   ```
-
-5. **Code implementieren:**
-   
-   Alle Code-Beispiele findest du in:
-   - [ANDROID_GUIDE.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/ANDROID_GUIDE.md)
-   
-   Kopiere der Reihe nach:
-   - `models/Note.kt`
-   - `models/SyncStatus.kt`
-   - `storage/NotesStorage.kt`
-   - `utils/DeviceIdGenerator.kt`
-   - `utils/NotificationHelper.kt`
-   - `utils/Extensions.kt`
-   - `utils/Constants.kt`
-   - UI Layouts aus dem Guide
-   - Activities (MainActivity, NoteEditorActivity, SettingsActivity)
-   - `sync/WebDavSyncService.kt`
-   - `sync/WifiSyncReceiver.kt`
-   - `sync/SyncWorker.kt`
-   - `adapters/NotesAdapter.kt`
-
-6. **AndroidManifest.xml anpassen:**
-   ```xml
-   <uses-permission android:name="android.permission.INTERNET" />
-   <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
-   <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
-   <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
-   
-   <application
-       ...
-       android:usesCleartextTraffic="true">
-   ```
-
-7. **Build & Run:**
-   ```
-   Build → Make Project
-   Run → Run 'app'
-   ```
-
-8. **In der App konfigurieren:**
-   - Einstellungen öffnen
-   - Server URL: `http://192.168.0.188:8080/`
-   - Username: `noteuser`
-   - Password: `SimpleNotes2025!`
-   - Heim-WLAN SSID: `DeinWLANName`
-   - "Verbindung testen" → sollte erfolgreich sein ✓
-
-### Option 2: Schritt-für-Schritt Implementation
-
-Folge dem [IMPLEMENTATION_PLAN.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/IMPLEMENTATION_PLAN.md) mit 6 Sprints:
-
-1. **Sprint 1:** Server & Foundation (bereits done ✓)
-2. **Sprint 2:** Basic UI (4-6h)
-3. **Sprint 3:** Settings & WebDAV (6h)
-4. **Sprint 4:** Auto-Sync (6h)
-5. **Sprint 5:** Conflicts & Errors (6h)
-6. **Sprint 6:** Polish & Testing (6h)
-
-## 🧪 Server testen
-
-Der Server läuft bereits. Teste ihn:
-
-```bash
-# Einfacher Test
-curl -u noteuser:SimpleNotes2025! http://localhost:8080/
-
-# Test-Notiz hochladen
-echo '{"id":"test-123","title":"Test","content":"Hello World","createdAt":1703001234567,"updatedAt":1703001234567,"deviceId":"test","syncStatus":"SYNCED"}' > test.json
-
-curl -u noteuser:SimpleNotes2025! \
-  -T test.json \
-  http://localhost:8080/test.json
-
-# Test-Notiz abrufen
-curl -u noteuser:SimpleNotes2025! http://localhost:8080/test.json
-
-# Löschen
-curl -u noteuser:SimpleNotes2025! \
-  -X DELETE \
-  http://localhost:8080/test.json
-```
-
-## 📊 Server Management
-
-```bash
-cd /home/liq/gitProjects/simple-notes-sync/server
-
-# Status
-docker-compose ps
-
-# Logs
-docker-compose logs -f
-
-# Stoppen
-docker-compose down
-
-# Neu starten
-docker-compose up -d
-
-# Daten ansehen
-ls -la notes-data/
-```
-
-## 🔧 Troubleshooting
-
-### Server nicht erreichbar von Android
-
-1. **Firewall prüfen:**
-   ```bash
-   sudo ufw status
-   sudo ufw allow 8080
-   ```
-
-2. **Ping-Test:**
-   ```bash
-   ping 192.168.0.188
-   ```
-
-3. **Port-Test:**
-   ```bash
-   telnet 192.168.0.188 8080
-   ```
-
-### Permission Denied in Android
-
-- Android 13+: POST_NOTIFICATIONS Permission akzeptieren
-- Internet Permission in Manifest vorhanden?
-- `usesCleartextTraffic="true"` gesetzt?
-
-## 📚 Weitere Hilfe
-
-- **Vollständige Doku:** [project-docs/simple-notes-sync](https://github.com/inventory69/project-docs/tree/main/simple-notes-sync)
-- **Android Code:** [ANDROID_GUIDE.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/ANDROID_GUIDE.md)
-- **Server Setup:** [SERVER_SETUP.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/SERVER_SETUP.md)
-- **Notifications:** [NOTIFICATIONS.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/NOTIFICATIONS.md)
 
 ---
 
-**Server Status:** ✅ Running on `http://192.168.0.188:8080/`
+## Voraussetzungen
-**Next:** Android App in Android Studio erstellen
-**Estimated Time:** 18-24 Stunden für vollständige App
 
-Viel Erfolg! 🚀
+- ✅ Android 8.0+ Smartphone/Tablet
+- ✅ WLAN-Verbindung
+- ✅ Eigener Server mit Docker (optional - für Self-Hosting)
+
+---
+
+## Option 1: Mit eigenem Server (Self-Hosted) 🏠
+
+### Schritt 1: WebDAV Server einrichten
+
+Auf deinem Server (z.B. Raspberry Pi, NAS, VPS):
+
+```bash
+# Repository klonen
+git clone https://github.com/inventory69/simple-notes-sync.git
+cd simple-notes-sync/server
+
+# Umgebungsvariablen konfigurieren
+cp .env.example .env
+nano .env
+```
+
+**In `.env` anpassen:**
+```env
+WEBDAV_PASSWORD=dein-sicheres-passwort-hier
+```
+
+**Server starten:**
+```bash
+docker compose up -d
+```
+
+**IP-Adresse finden:**
+```bash
+ip addr show | grep "inet " | grep -v 127.0.0.1
+```
+
+➡️ **Notiere dir:** `http://DEINE-SERVER-IP:8080/`
+
+---
+
+### Schritt 2: App installieren
+
+1. **APK herunterladen:** [Neueste Version](https://github.com/inventory69/simple-notes-sync/releases/latest)
+   - Wähle: `simple-notes-sync-vX.X.X-standard-universal.apk`
+   
+2. **Installation erlauben:**
+   - Android: Einstellungen → Sicherheit → "Unbekannte Quellen" für deinen Browser aktivieren
+   
+3. **APK öffnen und installieren**
+
+---
+
+### Schritt 3: App konfigurieren
+
+1. **App öffnen**
+
+2. **Einstellungen öffnen** (⚙️ Icon oben rechts)
+
+3. **Server-Einstellungen konfigurieren:**
+   
+   | Feld | Wert |
+   |------|------|
+   | **WebDAV Server URL** | `http://DEINE-SERVER-IP:8080/` |
+   | **Benutzername** | `noteuser` |
+   | **Passwort** | (dein Passwort aus `.env`) |
+   | **Gateway SSID** | Name deines WLAN-Netzwerks |
+
+   > **💡 Hinweis:** Gib nur die Base-URL ein (ohne `/notes`). Die App erstellt automatisch `/notes/` für JSON-Dateien und `/notes-md/` für Markdown-Export.
+
+4. **"Verbindung testen"** drücken
+   - ✅ Erfolg? → Weiter zu Schritt 4
+   - ❌ Fehler? → Siehe [Troubleshooting](#troubleshooting)
+
+5. **Auto-Sync aktivieren** (Toggle Switch)
+
+6. **Sync-Intervall wählen:**
+   - **15 Min** - Maximale Aktualität (~0.8% Akku/Tag)
+   - **30 Min** - Empfohlen (~0.4% Akku/Tag) ⭐
+   - **60 Min** - Maximale Akkulaufzeit (~0.2% Akku/Tag)
+
+---
+
+### Schritt 4: Erste Notiz erstellen
+
+1. Zurück zur Hauptansicht (← Pfeil)
+
+2. **"Notiz hinzufügen"** (+ Icon)
+
+3. Titel und Text eingeben
+
+4. **Speichern** (💾 Icon)
+
+5. **Warten auf Auto-Sync** (oder manuell: ⚙️ → "Jetzt synchronisieren")
+
+🎉 **Fertig!** Deine Notizen werden automatisch synchronisiert!
+
+---
+
+## Option 2: Nur lokale Notizen (kein Server) 📱
+
+Du kannst Simple Notes auch **ohne Server** nutzen:
+
+1. **App installieren** (siehe Schritt 2 oben)
+
+2. **Ohne Server-Konfiguration verwenden:**
+   - Notizen werden nur lokal gespeichert
+   - Kein Auto-Sync
+   - Perfekt für reine Offline-Nutzung
+
+---
+
+## 🔋 Akku-Optimierung deaktivieren
+
+Für zuverlässigen Auto-Sync:
+
+1. **Einstellungen** → **Apps** → **Simple Notes Sync**
+
+2. **Akku** → **Akkuverbrauch**
+
+3. Wähle: **"Nicht optimieren"** oder **"Unbeschränkt"**
+
+💡 **Hinweis:** Android Doze Mode kann trotzdem Sync im Standby verzögern (~60 Min). Das ist normal und betrifft alle Apps.
+
+---
+
+## 📊 Sync-Intervalle im Detail
+
+| Intervall | Syncs/Tag | Akku/Tag | Akku/Sync | Anwendungsfall |
+|-----------|-----------|----------|-----------|----------------|
+| **15 Min** | ~96 | ~0.8% (~23 mAh) | ~0.008% | ⚡ Maximal aktuell (mehrere Geräte) |
+| **30 Min** | ~48 | ~0.4% (~12 mAh) | ~0.008% | ✓ **Empfohlen** - ausgewogen |
+| **60 Min** | ~24 | ~0.2% (~6 mAh) | ~0.008% | 🔋 Maximale Akkulaufzeit |
+
+---
+
+## 🐛 Troubleshooting
+
+### Verbindungstest schlägt fehl
+
+**Problem:** "Verbindung fehlgeschlagen" beim Test
+
+**Lösungen:**
+
+1. **Server läuft?**
+   ```bash
+   docker compose ps
+   # Sollte "Up" zeigen
+   ```
+
+2. **Gleiche WLAN?**
+   - Smartphone und Server müssen im selben Netzwerk sein
+   - Prüfe SSID in App-Einstellungen
+
+3. **IP-Adresse korrekt?**
+   ```bash
+   ip addr show | grep "inet "
+   # Prüfe ob IP in URL stimmt
+   ```
+
+4. **Firewall?**
+   ```bash
+   # Port 8080 öffnen (falls Firewall aktiv)
+   sudo ufw allow 8080/tcp
+   ```
+
+5. **Server-Logs prüfen:**
+   ```bash
+   docker compose logs -f
+   ```
+
+---
+
+### Auto-Sync funktioniert nicht
+
+**Problem:** Notizen werden nicht automatisch synchronisiert
+
+**Lösungen:**
+
+1. **Auto-Sync aktiviert?**
+   - ⚙️ Einstellungen → Toggle "Auto-Sync" muss **AN** sein
+
+2. **Akku-Optimierung deaktiviert?**
+   - Siehe [Akku-Optimierung](#-akku-optimierung-deaktivieren)
+
+3. **Im richtigen WLAN?**
+   - Sync funktioniert nur wenn SSID = Gateway SSID
+   - Prüfe aktuelle SSID in Android-Einstellungen
+
+4. **Manuell testen:**
+   - ⚙️ Einstellungen → "Jetzt synchronisieren"
+   - Funktioniert das? → Auto-Sync sollte auch funktionieren
+
+---
+
+### Notizen werden nicht angezeigt
+
+**Problem:** Nach Installation sind keine Notizen da, obwohl welche auf dem Server liegen
+
+**Lösung:**
+
+1. **Einmalig manuell synchronisieren:**
+   - ⚙️ Einstellungen → "Jetzt synchronisieren"
+
+2. **Server-Daten prüfen:**
+   ```bash
+   docker compose exec webdav ls -la /data/
+   # Sollte .json Dateien zeigen
+   ```
+
+---
+
+### Fehler beim Sync
+
+**Problem:** Fehlermeldung beim Synchronisieren
+
+**Lösungen:**
+
+1. **"401 Unauthorized"** → Passwort falsch
+   - Prüfe Passwort in App-Einstellungen
+   - Vergleiche mit `.env` auf Server
+
+2. **"404 Not Found"** → URL falsch
+   - Sollte enden mit `/` (z.B. `http://192.168.1.100:8080/`)
+
+3. **"Network error"** → Keine Verbindung
+   - Siehe [Verbindungstest schlägt fehl](#verbindungstest-schlägt-fehl)
+
+---
+
+## 📱 Updates
+
+### Automatisch mit Obtainium (empfohlen)
+
+1. **[Obtainium installieren](https://github.com/ImranR98/Obtanium/releases/latest)**
+
+2. **App hinzufügen:**
+   - URL: `https://github.com/inventory69/simple-notes-sync`
+   - Auto-Update aktivieren
+
+3. **Fertig!** Obtainium benachrichtigt dich bei neuen Versionen
+
+### Manuell
+
+1. Neue APK von [Releases](https://github.com/inventory69/simple-notes-sync/releases/latest) herunterladen
+
+2. Installieren (überschreibt alte Version)
+
+3. Alle Daten bleiben erhalten!
+
+---
+
+## 🆘 Weitere Hilfe
+
+- **GitHub Issues:** [Problem melden](https://github.com/inventory69/simple-notes-sync/issues)
+- **Vollständige Docs:** [DOCS.md](DOCS.md)
+- **Server Setup Details:** [server/README.md](server/README.md)
+
+---
+
+**Version:** 1.1.0 · **Erstellt:** Dezember 2025

README.en.md

@@ -0,0 +1,104 @@
+# Simple Notes Sync 📝
+
+> Minimalist offline notes with auto-sync to your own server
+
+[![Android](https://img.shields.io/badge/Android-8.0%2B-green.svg)](https://www.android.com/)
+[![Material Design 3](https://img.shields.io/badge/Material-Design%203-green.svg)](https://m3.material.io/)
+[![License](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)
+
+[<img src="https://gitlab.com/IzzyOnDroid/repo/-/raw/master/assets/IzzyOnDroid.png" alt="Get it on IzzyOnDroid" height="80">](https://apt.izzysoft.de/fdroid/index/apk/dev.dettmer.simplenotes)
+
+**📱 [APK Download](https://github.com/inventory69/simple-notes-sync/releases/latest)** · **📖 [Documentation](docs/DOCS.en.md)** · **🚀 [Quick Start](QUICKSTART.en.md)**
+
+**🌍 Languages:** [Deutsch](README.md) · **English**
+
+---
+
+## 📱 Screenshots
+
+<p align="center">
+  <img src="fastlane/metadata/android/de-DE/images/phoneScreenshots/1.jpg" width="250" alt="Notes list">
+  <img src="fastlane/metadata/android/de-DE/images/phoneScreenshots/2.jpg" width="250" alt="Edit note">
+  <img src="fastlane/metadata/android/de-DE/images/phoneScreenshots/3.jpg" width="250" alt="Settings">
+</p>
+
+---
+
+## ✨ Highlights
+
+- 📝 **Offline-first** - Works without internet
+- 🔄 **Auto-sync** - Home WiFi only (15/30/60 min)
+- 🔒 **Self-hosted** - Your data stays with you (WebDAV)
+- 💾 **Local backup** - Export/Import as JSON file
+- 🖥️ **Desktop integration** - Markdown export for VS Code, Typora, etc.
+- 🔋 **Battery-friendly** - ~0.2-0.8% per day
+- 🎨 **Material Design 3** - Dark mode & dynamic colors
+
+➡️ **Complete feature list:** [FEATURES.en.md](docs/FEATURES.en.md)
+
+---
+
+## 🚀 Quick Start
+
+### 1. Server Setup (5 minutes)
+
+```bash
+git clone https://github.com/inventory69/simple-notes-sync.git
+cd simple-notes-sync/server
+cp .env.example .env
+# Set password in .env
+docker compose up -d
+```
+
+➡️ **Details:** [Server Setup Guide](server/README.en.md)
+
+### 2. App Installation (2 minutes)
+
+1. [Download APK](https://github.com/inventory69/simple-notes-sync/releases/latest)
+2. Install & open
+3. ⚙️ Settings → Configure server:
+   - **URL:** `http://YOUR-SERVER-IP:8080/` _(base URL only!)_
+   - **User:** `noteuser`
+   - **Password:** _(from .env)_
+   - **WiFi:** _(your network name)_
+4. **Test connection** → Enable auto-sync
+5. Done! 🎉
+
+➡️ **Detailed guide:** [QUICKSTART.en.md](QUICKSTART.en.md)
+
+---
+
+## 📚 Documentation
+
+| Document | Content |
+|----------|---------|
+| **[QUICKSTART.en.md](QUICKSTART.en.md)** | Step-by-step installation |
+| **[FEATURES.en.md](docs/FEATURES.en.md)** | Complete feature list |
+| **[BACKUP.en.md](docs/BACKUP.en.md)** | Backup & restore guide |
+| **[DESKTOP.en.md](docs/DESKTOP.en.md)** | Desktop integration (Markdown) |
+---
+
+## 🛠️ Development
+
+```bash
+cd android
+./gradlew assembleStandardRelease
+```
+
+➡️ **Build guide:** [DOCS.en.md](docs/DOCS.en.md#-build--deployment)
+
+---
+
+## 🤝 Contributing
+
+Contributions welcome! See [CONTRIBUTING.md](CONTRIBUTING.md)
+
+---
+
+## 📄 License
+
+MIT License - see [LICENSE](LICENSE)
+
+---
+
+**v1.3.2** · Built with ❤️ using Kotlin + Material Design 3

README.md

@@ -1,130 +1,100 @@
 # Simple Notes Sync 📝
 
-> **Minimalistische Android Notiz-App mit automatischer WLAN-Synchronisierung**
+> Minimalistische Offline-Notizen mit Auto-Sync zu deinem eigenen Server
 
 [![Android](https://img.shields.io/badge/Android-8.0%2B-green.svg)](https://www.android.com/)
-[![Kotlin](https://img.shields.io/badge/Kotlin-1.9%2B-blue.svg)](https://kotlinlang.org/)
 [![Material Design 3](https://img.shields.io/badge/Material-Design%203-green.svg)](https://m3.material.io/)
 [![License](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)
 
-Schlanke Offline-Notizen ohne Schnickschnack - deine Daten bleiben bei dir. Automatische Synchronisierung zu deinem eigenen WebDAV-Server, kein Google, kein Microsoft, keine Cloud.
+[<img src="https://gitlab.com/IzzyOnDroid/repo/-/raw/master/assets/IzzyOnDroid.png" alt="Get it on IzzyOnDroid" height="80">](https://apt.izzysoft.de/fdroid/index/apk/dev.dettmer.simplenotes)
 
-## ✨ Features
+**📱 [APK Download](https://github.com/inventory69/simple-notes-sync/releases/latest)** · **📖 [Dokumentation](docs/DOCS.md)** · **🚀 [Quick Start](QUICKSTART.md)**
 
-- 📝 **Offline-First** - Notizen lokal gespeichert, immer verfügbar
+**🌍 Sprachen:** **Deutsch** · [English](README.en.md)
-- 🔄 **Auto-Sync** - Konfigurierbare Intervalle (15/30/60 Min.) mit ~0.2-0.8% Akku/Tag
-- 🏠 **Self-Hosted** - Deine Daten auf deinem Server (WebDAV)
-- 🎨 **Material Design 3** - Modern & Dynamic Theming
-- 🔋 **Akkuschonend** - Optimiert für Hintergrund-Synchronisierung
-- 🔐 **Privacy-First** - Kein Tracking, keine Analytics, keine Cloud
-- 🚫 **Keine Berechtigungen** - Nur Internet für WebDAV Sync
 
-## 📥 Quick Download
+---
 
-**Android APK:** [📱 Neueste Version herunterladen](https://github.com/inventory69/simple-notes-sync/releases/latest)
+## 📱 Screenshots
 
-💡 **Tipp:** Nutze [Obtainium](https://github.com/ImranR98/Obtainium) für automatische Updates!
+<p align="center">
+  <img src="fastlane/metadata/android/de-DE/images/phoneScreenshots/1.jpg" width="250" alt="Notizliste">
+  <img src="fastlane/metadata/android/de-DE/images/phoneScreenshots/2.jpg" width="250" alt="Notiz bearbeiten">
+  <img src="fastlane/metadata/android/de-DE/images/phoneScreenshots/3.jpg" width="250" alt="Einstellungen">
+</p>
+
+---
+
+## ✨ Highlights
+
+- 📝 **Offline-First** - Funktioniert ohne Internet
+- 🔄 **Auto-Sync** - Nur im Heim-WLAN (15/30/60 Min)
+- 🔒 **Self-Hosted** - Deine Daten bleiben bei dir (WebDAV)
+- 💾 **Lokales Backup** - Export/Import als JSON-Datei
+- 🖥️ **Desktop-Integration** - Markdown-Export für VS Code, Typora, etc.
+- 🔋 **Akkuschonend** - ~0.2-0.8% pro Tag
+- 🎨 **Material Design 3** - Dark Mode & Dynamic Colors
+
+➡️ **Vollständige Feature-Liste:** [FEATURES.md](docs/FEATURES.md)
 
 ---
 
 ## 🚀 Schnellstart
 
-### 1️⃣ WebDAV Server starten
+### 1. Server Setup (5 Minuten)
 
-```fish
+```bash
-cd server
+git clone https://github.com/inventory69/simple-notes-sync.git
+cd simple-notes-sync/server
 cp .env.example .env
-# Passwort in .env anpassen
+# Passwort in .env setzen
 docker compose up -d
 ```
 
-### 2️⃣ App installieren & konfigurieren
+➡️ **Details:** [Server Setup Guide](server/README.md)
 
-1. APK herunterladen und installieren
+### 2. App Installation (2 Minuten)
-2. App öffnen → **Einstellungen** (⚙️)
-3. Server konfigurieren:
-   - URL: `http://192.168.0.XXX:8080/notes`
-   - Benutzername: `noteuser`
-   - Passwort: (aus `.env`)
-4. **Auto-Sync aktivieren**
-5. **Sync-Intervall wählen** (15/30/60 Min.)
 
-**Fertig!** Notizen werden automatisch synchronisiert 🎉
+1. [APK herunterladen](https://github.com/inventory69/simple-notes-sync/releases/latest)
+2. Installieren & öffnen
+3. ⚙️ Einstellungen → Server konfigurieren:
+   - **URL:** `http://DEINE-SERVER-IP:8080/` _(nur Base-URL!)_
+   - **User:** `noteuser`
+   - **Passwort:** _(aus .env)_
+   - **WLAN:** _(dein Netzwerk-Name)_
+4. **Verbindung testen** → Auto-Sync aktivieren
+5. Fertig! 🎉
+
+➡️ **Ausführliche Anleitung:** [QUICKSTART.md](QUICKSTART.md)
 
 ---
 
-## ⚙️ Sync-Intervalle
+## 📚 Dokumentation
 
-| Intervall | Akku/Tag | Anwendungsfall |
+| Dokument | Inhalt |
-|-----------|----------|----------------|
+|----------|--------|
-| **15 Min** | ~0.8% (~23 mAh) | ⚡ Maximale Aktualität |
+| **[QUICKSTART.md](QUICKSTART.md)** | Schritt-für-Schritt Installation |
-| **30 Min** | ~0.4% (~12 mAh) | ✓ Empfohlen - Ausgewogen |
+| **[FEATURES.md](docs/FEATURES.md)** | Vollständige Feature-Liste |
-| **60 Min** | ~0.2% (~6 mAh) | 🔋 Maximale Akkulaufzeit |
+| **[BACKUP.md](docs/BACKUP.md)** | Backup & Wiederherstellung |
-
+| **[DESKTOP.md](docs/DESKTOP.md)** | Desktop-Integration (Markdown) |
-💡 **Hinweis:** Android Doze Mode kann Sync im Standby auf ~60 Min. verzögern (betrifft alle Apps).
+| **[DOCS.md](docs/DOCS.md)** | Technische Details & Troubleshooting |
+| **[CHANGELOG.md](CHANGELOG.md)** | Versionshistorie |
 
 ---
 
-## <EFBFBD> Neue Features in v1.1.0
+## 🛠️ Entwicklung
 
-### Konfigurierbare Sync-Intervalle
+```bash
-- ⏱️ Wählbare Intervalle: 15/30/60 Minuten
-- 📊 Transparente Akkuverbrauchs-Anzeige
-- <20> Sofortige Anwendung ohne App-Neustart
-
-### Über-Sektion
-- <20> App-Version & Build-Datum
-- 🌐 Links zu GitHub Repo & Entwickler
-- ⚖️ Lizenz-Information
-
-### Verbesserungen
-- 🎯 Benutzerfreundliche Doze-Mode Erklärung
-- 🔕 Keine störenden Sync-Fehler Toasts im Hintergrund
-- 📝 Erweiterte Debug-Logs für Troubleshooting
-
----
-
-## 🛠️ Selbst bauen
-
-```fish
 cd android
 ./gradlew assembleStandardRelease
-# APK: android/app/build/outputs/apk/standard/release/
 ```
 
----
+➡️ **Build-Anleitung:** [DOCS.md](docs/DOCS.md#-build--deployment)
-
-## 🐛 Troubleshooting
-
-### Auto-Sync funktioniert nicht
-
-1. **Akku-Optimierung deaktivieren**
-   - Einstellungen → Apps → Simple Notes → Akku → Nicht optimieren
-2. **WLAN-Verbindung prüfen**
-   - Funktioniert nur im selben Netzwerk wie Server
-3. **Server-Status checken**
-   - Settings → "Verbindung testen"
-
-### Server nicht erreichbar
-
-```fish
-# Status prüfen
-docker compose ps
-
-# Logs ansehen
-docker compose logs -f
-
-# IP-Adresse finden
-ip addr show | grep "inet " | grep -v 127.0.0.1
-```
-
-Mehr Details: [📖 Dokumentation](DOCS.md)
 
 ---
 
 ## 🤝 Contributing
 
-Contributions sind willkommen! Bitte öffne ein Issue oder Pull Request.
+Beiträge willkommen! Siehe [CONTRIBUTING.md](CONTRIBUTING.md)
 
 ---
 
@@ -134,4 +104,4 @@ MIT License - siehe [LICENSE](LICENSE)
 
 ---
 
-**Version:** 1.1.0 · **Status:** ✅ Produktiv · **Gebaut mit:** Kotlin + Material Design 3
+**v1.3.2** · Built with ❤️ using Kotlin + Material Design 3

README.old.md

@@ -1,335 +0,0 @@
-# Simple Notes Sync 📝
-
-> Minimalistische Android-App für Offline-Notizen mit automatischer WLAN-Synchronisierung
-
-Eine schlanke Notiz-App ohne Schnickschnack - perfekt für schnelle Gedanken, die automatisch zu Hause synchronisiert werden.
-
----
-
-## ✨ Features
-
-- 📝 **Offline-first** - Notizen werden lokal gespeichert und sind immer verfügbar
-- 🔄 **Auto-Sync** - Automatische Synchronisierung wenn du im Heimnetzwerk bist
-- 🏠 **WebDAV Server** - Deine Daten bleiben bei dir (Docker-Container)
-- 🔋 **Akkuschonend** - Nur ~0.4% Akkuverbrauch pro Tag
-- 🚫 **Keine Cloud** - Keine Google, keine Microsoft, keine Drittanbieter
-- 🔐 **Privacy** - Keine Tracking, keine Analytics, keine Standort-Berechtigungen
-
----
-
-## 📥 Installation
-
-### Android App
-
-**Option 1: APK herunterladen**
-
-1. Neueste [Release](../../releases/latest) öffnen
-2. `app-debug.apk` herunterladen
-3. APK auf dem Handy installieren
-
-**Option 2: Selbst bauen**
-
-```bash
-cd android
-./gradlew assembleDebug
-# APK: android/app/build/outputs/apk/debug/app-debug.apk
-```
-
-### WebDAV Server
-
-Der Server läuft als Docker-Container und speichert deine Notizen.
-
-```bash
-cd server
-cp .env.example .env
-nano .env  # Passwort anpassen!
-docker-compose up -d
-```
-
-**Server testen:**
-```bash
-curl -u noteuser:dein_passwort http://192.168.0.XXX:8080/
-```
-
----
-
-## 🚀 Schnellstart
-
-1. **Server starten** (siehe oben)
-2. **App installieren** und öffnen
-3. **Einstellungen öffnen** (⚙️ Symbol oben rechts)
-4. **Server konfigurieren:**
-   - Server-URL: `http://192.168.0.XXX:8080/notes`
-   - Benutzername: `noteuser`
-   - Passwort: (aus `.env` Datei)
-   - Auto-Sync: **AN**
-5. **Fertig!** Notizen werden jetzt automatisch synchronisiert
-
----
-
-## 💡 Wie funktioniert Auto-Sync?
-
-Die App prüft **alle 30 Minuten**, ob:
-- ✅ WLAN verbunden ist
-- ✅ Server im gleichen Netzwerk erreichbar ist
-- ✅ Neue Notizen vorhanden sind
-
-Wenn alle Bedingungen erfüllt → **Automatische Synchronisierung**
-
-**Wichtig:** Funktioniert nur im selben Netzwerk wie der Server (kein Internet-Zugriff nötig!)
-
----
-
-## 🔋 Akkuverbrauch
-
-| Komponente | Verbrauch/Tag |
-|------------|---------------|
-| WorkManager (alle 30 Min) | ~0.3% |
-| Netzwerk-Checks | ~0.1% |
-| **Total** | **~0.4%** |
-
-Bei einem 3000 mAh Akku entspricht das ~12 mAh pro Tag.
-
----
-
-## 📱 Screenshots
-
-_TODO: Screenshots hinzufügen_
-
----
-
-## 🛠️ Technische Details
-
-Mehr Infos zur Architektur und Implementierung findest du in der [technischen Dokumentation](DOCS.md).
-
-**Stack:**
-- **Android:** Kotlin, Material Design 3, WorkManager
-- **Server:** Docker, WebDAV (bytemark/webdav)
-- **Sync:** Sardine Android (WebDAV Client)
-
----
-
-## 📄 Lizenz
-
-[Lizenz hier einfügen]
-
----
-
-## 🤝 Beitragen
-
-Contributions sind willkommen! Bitte öffne ein Issue oder Pull Request.
-
----
-
-## 📄 Lizenz
-
-MIT License - siehe [LICENSE](LICENSE)
-
----
-
-**Projekt Start:** 19. Dezember 2025  
-**Status:** ✅ Funktional & Produktiv
-
-## 📖 Dokumentation
-
-### In diesem Repository:
-
-- **[QUICKSTART.md](QUICKSTART.md)** - Schnellstart-Anleitung
-- **[server/README.md](server/README.md)** - Server-Verwaltung
-
-### Vollständige Dokumentation (project-docs):
-
-- [README.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/README.md) - Projekt-Übersicht & Architektur
-- [IMPLEMENTATION_PLAN.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/IMPLEMENTATION_PLAN.md) - Detaillierter Sprint-Plan
-- [SERVER_SETUP.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/SERVER_SETUP.md) - Server-Setup Details
-- [ANDROID_GUIDE.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/ANDROID_GUIDE.md) - 📱 Kompletter Android-Code
-- [NOTIFICATIONS.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/NOTIFICATIONS.md) - Notification-System Details
-- [WINDOWS_SETUP.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/WINDOWS_SETUP.md) - 🪟 Windows + Android Studio Setup
-- [CODE_REFERENCE.md](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/CODE_REFERENCE.md) - Schnelle Code-Referenz
-
-## ⚙️ Server Konfiguration
-
-**Standard-Credentials:**
-- Username: `noteuser`
-- Password: Siehe `.env` im `server/` Verzeichnis
-
-**Server-URL:**
-- Lokal: `http://localhost:8080/`
-- Im Netzwerk: `http://YOUR_IP:8080/`
-
-IP-Adresse finden:
-```bash
-ip addr show | grep "inet " | grep -v 127.0.0.1
-```
-
-## 📱 Android App Setup
-
-### Vorraussetzungen
-
-- Android Studio Hedgehog (2023.1.1) oder neuer
-- JDK 17
-- Min SDK 24 (Android 7.0)
-- Target SDK 34 (Android 14)
-
-### In App konfigurieren
-
-1. App starten
-2. Einstellungen öffnen
-3. Server-URL eintragen (z.B. `http://192.168.1.100:8080/`)
-4. Username & Passwort eingeben
-5. Heim-WLAN SSID eingeben
-6. "Verbindung testen"
-
-## 🔧 Entwicklung
-
-### Server-Management
-
-```bash
-# Status prüfen
-docker-compose ps
-
-# Logs anschauen
-docker-compose logs -f
-
-# Neustarten
-docker-compose restart
-
-# Stoppen
-docker-compose down
-```
-
-### Android-Build
-
-```bash
-cd android
-./gradlew assembleDebug
-
-# APK Location:
-# app/build/outputs/apk/debug/app-debug.apk
-```
-
-## 🧪 Testing
-
-### Server-Test
-
-```bash
-# Testdatei hochladen
-echo '{"id":"test","title":"Test","content":"Hello"}' > test.json
-curl -u noteuser:password -T test.json http://localhost:8080/test.json
-
-# Datei abrufen
-curl -u noteuser:password http://localhost:8080/test.json
-
-# Datei löschen
-curl -u noteuser:password -X DELETE http://localhost:8080/test.json
-```
-
-### Android-App
-
-1. Notiz erstellen → speichern → in Liste sichtbar ✓
-2. WLAN verbinden → Auto-Sync ✓
-3. Server offline → Fehlermeldung ✓
-4. Konflikt-Szenario → Auflösung ✓
-
-## 📦 Deployment
-
-### Server (Production)
-
-**Option 1: Lokaler Server (Raspberry Pi, etc.)**
-```bash
-docker-compose up -d
-```
-
-**Option 2: VPS (DigitalOcean, Hetzner, etc.)**
-```bash
-# Mit HTTPS (empfohlen)
-# Zusätzlich: Reverse Proxy (nginx/Caddy) + Let's Encrypt
-```
-
-### Android App
-
-```bash
-# Release Build
-./gradlew assembleRelease
-
-# APK signieren
-# Play Store Upload oder Direct Install
-```
-
-## 🔐 Security
-
-**Entwicklung:**
-- ✅ HTTP Basic Auth
-- ✅ Nur im lokalen Netzwerk
-
-**Produktion:**
-- ⚠️ HTTPS mit SSL/TLS (empfohlen)
-- ⚠️ Starkes Passwort
-- ⚠️ Firewall-Regeln
-- ⚠️ VPN für externen Zugriff
-
-## 🐛 Troubleshooting
-
-### Server startet nicht
-
-```bash
-# Port bereits belegt?
-sudo netstat -tlnp | grep 8080
-
-# Logs checken
-docker-compose logs webdav
-```
-
-### Android kann nicht verbinden
-
-- Ist Android im gleichen WLAN?
-- Ist die Server-IP korrekt?
-- Firewall blockiert Port 8080?
-- Credentials korrekt?
-
-```bash
-# Ping zum Server
-ping YOUR_SERVER_IP
-
-# Port erreichbar?
-telnet YOUR_SERVER_IP 8080
-```
-
-## 📝 TODO / Roadmap
-
-### Version 1.0 (MVP)
-- [x] Docker WebDAV Server
-- [ ] Android Basic CRUD
-- [ ] Auto-Sync bei WLAN
-- [ ] Error Handling
-- [ ] Notifications
-
-### Version 1.1
-- [ ] Suche
-- [ ] Dark Mode
-- [ ] Markdown-Support
-
-### Version 2.0
-- [ ] Desktop-Client (Flutter Desktop)
-- [ ] Tags/Kategorien
-- [ ] Verschlüsselung
-- [ ] Shared Notes
-
-## 📄 License
-
-MIT License - siehe [LICENSE](LICENSE)
-
-## 👤 Author
-
-Created for personal use - 2025
-
-## 🙏 Acknowledgments
-
-- [bytemark/webdav](https://hub.docker.com/r/bytemark/webdav) - Docker WebDAV Server
-- [Sardine Android](https://github.com/thegrizzlylabs/sardine-android) - WebDAV Client
-- [Android WorkManager](https://developer.android.com/topic/libraries/architecture/workmanager) - Background Tasks
-
----
-
-**Project Start:** 19. Dezember 2025
-**Status:** 🚧 In Development

android/.editorconfig

@@ -0,0 +1,61 @@
+# ⚡ v1.3.1: EditorConfig for ktlint
+# https://editorconfig.org
+
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_size = 4
+indent_style = space
+insert_final_newline = true
+max_line_length = 120
+trim_trailing_whitespace = true
+
+[*.{kt,kts}]
+# ktlint rules
+ktlint_code_style = android_studio
+ktlint_standard_no-wildcard-imports = disabled
+ktlint_standard_package-name = enabled
+ktlint_standard_filename = enabled
+ktlint_standard_class-naming = enabled
+ktlint_standard_function-naming = enabled
+ktlint_standard_property-naming = enabled
+ktlint_standard_backing-property-naming = enabled
+ktlint_standard_enum-entry-name-case = enabled
+ktlint_standard_multiline-if-else = enabled
+ktlint_standard_no-empty-class-body = enabled
+ktlint_standard_no-empty-first-line-in-class-body = enabled
+ktlint_standard_blank-line-before-declaration = enabled
+ktlint_standard_context-receiver-wrapping = enabled
+ktlint_standard_function-expression-body = disabled
+ktlint_standard_function-literal = enabled
+ktlint_standard_function-type-modifier-spacing = enabled
+ktlint_standard_kdoc-wrapping = enabled
+ktlint_standard_modifier-list-spacing = enabled
+ktlint_standard_no-blank-line-in-list = enabled
+ktlint_standard_no-consecutive-comments = disabled
+ktlint_standard_no-single-line-block-comment = enabled
+ktlint_standard_parameter-list-spacing = enabled
+ktlint_standard_parameter-list-wrapping = enabled
+ktlint_standard_property-wrapping = enabled
+ktlint_standard_spacing-between-function-name-and-opening-parenthesis = enabled
+ktlint_standard_statement-wrapping = enabled
+ktlint_standard_string-template-indent = disabled
+ktlint_standard_try-catch-finally-spacing = enabled
+ktlint_standard_type-argument-list-spacing = enabled
+ktlint_standard_type-parameter-list-spacing = enabled
+ktlint_standard_value-argument-comment = enabled
+ktlint_standard_value-parameter-comment = enabled
+
+[*.md]
+trim_trailing_whitespace = false
+
+[*.{xml,json}]
+indent_size = 2
+
+[*.yml]
+indent_size = 2
+
+[Makefile]
+indent_style = tab

android/.gitignore

@@ -13,3 +13,8 @@
 .externalNativeBuild
 .cxx
 local.properties
+
+# Signing configuration (contains sensitive keys)
+key.properties
+*.jks
+*.keystore

android/LOCAL_BUILDS.md

@@ -0,0 +1,157 @@
+# Lokale Gradle Builds mit Release-Signierung
+
+Dieses Dokument erklärt, wie du lokal signierte APKs erstellst, die mit den GitHub Release-APKs kompatibel sind.
+
+## Problem
+
+- **GitHub Actions** erstellt signierte Release-APKs mit dem Production-Keystore
+- **Lokale Debug-Builds** verwenden einen temporären Debug-Key
+- ❌ **Resultat:** Nutzer können lokale Debug-APKs NICHT über Release-APKs installieren (Signature Mismatch!)
+
+## Lösung: Lokale Release-Builds mit Production-Key
+
+### 1️⃣ Keystore-Konfiguration einrichten
+
+Du hast bereits den Keystore: `/android/app/simple-notes-release.jks`
+
+Erstelle eine `key.properties` Datei im `/android/` Ordner:
+
+```bash
+cd /home/liq/gitProjects/simple-notes-sync/android
+cp key.properties.example key.properties
+```
+
+Bearbeite `key.properties` mit den echten Werten:
+
+```properties
+storeFile=simple-notes-release.jks
+storePassword=<dein-keystore-password>
+keyAlias=<dein-key-alias>
+keyPassword=<dein-key-password>
+```
+
+**Wichtig:** Die Werte müssen **exakt** mit den GitHub Secrets übereinstimmen:
+- `KEYSTORE_PASSWORD` → `storePassword`
+- `KEY_ALIAS` → `keyAlias`
+- `KEY_PASSWORD` → `keyPassword`
+
+### 2️⃣ Lokal signierte Release-APKs bauen
+
+```bash
+cd android
+./gradlew assembleStandardRelease
+```
+
+Die signierten APKs findest du dann hier:
+```
+android/app/build/outputs/apk/standard/release/
+├── app-standard-universal-release.apk
+├── app-standard-arm64-v8a-release.apk
+└── app-standard-armeabi-v7a-release.apk
+```
+
+### 3️⃣ F-Droid Flavor bauen (optional)
+
+```bash
+./gradlew assembleFdroidRelease
+```
+
+### 4️⃣ Beide Flavors gleichzeitig bauen
+
+```bash
+./gradlew assembleStandardRelease assembleFdroidRelease
+```
+
+## Verifizierung der Signatur
+
+Um zu prüfen, ob dein lokaler Build die gleiche Signatur wie die Release-Builds hat:
+
+```bash
+# Signatur von lokalem Build anzeigen
+keytool -printcert -jarfile app/build/outputs/apk/standard/release/app-standard-universal-release.apk
+
+# Signatur von GitHub Release-APK anzeigen (zum Vergleich)
+keytool -printcert -jarfile ~/Downloads/simple-notes-sync-v1.1.0-standard-universal.apk
+```
+
+Die **SHA256** Fingerprints müssen **identisch** sein!
+
+## Troubleshooting
+
+### ❌ Build schlägt fehl: "Keystore not found"
+
+**Problem:** `key.properties` oder Keystore-Datei fehlt
+
+**Lösung:** 
+1. Prüfe, ob `key.properties` existiert: `ls -la key.properties`
+2. Prüfe, ob der Keystore existiert: `ls -la app/simple-notes-release.jks`
+
+### ❌ "Signature mismatch" beim Update
+
+**Problem:** Der lokale Build verwendet einen anderen Key als die Release-Builds
+
+**Lösung:**
+1. Vergleiche die Signaturen mit `keytool` (siehe oben)
+2. Stelle sicher, dass `key.properties` die **exakten** GitHub Secret-Werte enthält
+3. Deinstalliere die alte Version und installiere die neue (als letzter Ausweg)
+
+### ❌ Build verwendet Debug-Signatur
+
+**Problem:** `build.gradle.kts` findet `key.properties` nicht
+
+**Lösung:**
+```bash
+# Prüfe, ob die Datei im richtigen Verzeichnis liegt
+ls -la android/key.properties  # ✅ Richtig
+ls -la android/app/key.properties  # ❌ Falsch
+```
+
+## Sicherheitshinweise
+
+⚠️ **NIEMALS** diese Dateien committen:
+- `key.properties` (in `.gitignore`)
+- `*.jks` / `*.keystore` (in `.gitignore`)
+
+✅ **Schon in `.gitignore`:**
+```gitignore
+key.properties
+*.jks
+*.keystore
+```
+
+⚠️ Die GitHub Secrets (`KEYSTORE_PASSWORD`, etc.) und die lokale `key.properties` müssen **synchron** bleiben!
+
+## Workflow-Vergleich
+
+### GitHub Actions Build
+```yaml
+- Lädt Keystore aus Base64 Secret
+- Erstellt key.properties aus Secrets
+- Baut mit: ./gradlew assembleStandardRelease
+- ✅ Produktions-signiert
+```
+
+### Lokaler Build
+```bash
+# Mit key.properties konfiguriert:
+./gradlew assembleStandardRelease
+# ✅ Produktions-signiert (gleiche Signatur wie GitHub!)
+
+# Ohne key.properties:
+./gradlew assembleStandardRelease
+# ⚠️ Debug-signiert (inkompatibel mit Releases!)
+```
+
+## Quick Reference
+
+```bash
+# Release-APK bauen (signiert, klein, optimiert)
+./gradlew assembleStandardRelease
+
+# Debug-APK bauen (unsigniert, groß, debuggable)
+./gradlew assembleStandardDebug
+
+# APK per HTTP Server verteilen
+cd app/build/outputs/apk/standard/release
+python3 -m http.server 8892
+```

android/app/build.gradle.kts

@@ -1,6 +1,9 @@
 plugins {
     alias(libs.plugins.android.application)
     alias(libs.plugins.kotlin.android)
+    // ⚡ v1.3.1: ktlint deaktiviert wegen Parser-Problemen, aktivieren in v1.4.0
+    // alias(libs.plugins.ktlint)
+    alias(libs.plugins.detekt)
 }
 
 import java.util.Properties
@@ -17,8 +20,8 @@ android {
         applicationId = "dev.dettmer.simplenotes"
         minSdk = 24
         targetSdk = 36
-        versionCode = 2  // 🔥 F-Droid Release v1.1.0
+        versionCode = 10  // 🚀 v1.3.2: Lint-Cleanup "Clean Slate"
-        versionName = "1.1.0"  // 🔥 Configurable Sync Interval + About Section
+        versionName = "1.3.2"  // 🚀 v1.3.2: Code-Qualität-Release (alle einfachen Lint-Issues behoben)
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
         
@@ -26,23 +29,21 @@ android {
         buildConfigField("String", "BUILD_DATE", "\"${getBuildDate()}\"")
     }
     
-    // Enable multiple APKs per ABI for smaller downloads
+    // Disable Google dependency metadata for F-Droid/IzzyOnDroid compatibility
-    splits {
+    dependenciesInfo {
-        abi {
+        includeInApk = false  // Removes DEPENDENCY_INFO_BLOCK from APK
-            isEnable = true
+        includeInBundle = false  // Also disable for AAB (Google Play)
-            reset()
-            include("armeabi-v7a", "arm64-v8a")
-            isUniversalApk = true  // Also generate universal APK
-        }
     }
     
     // Product Flavors for F-Droid and standard builds
+    // Note: APK splits are disabled to ensure single APK output
     flavorDimensions += "distribution"
     productFlavors {
         create("fdroid") {
             dimension = "distribution"
             // F-Droid builds have no proprietary dependencies
             // All dependencies in this project are already FOSS-compatible
+            // No APK splits - F-Droid expects single universal APK
         }
         
         create("standard") {
@@ -69,6 +70,16 @@ android {
     }
 
     buildTypes {
+        debug {
+            // ⚡ v1.3.1: Debug-Builds können parallel zur Release-App installiert werden
+            applicationIdSuffix = ".debug"
+            versionNameSuffix = "-debug"
+            isDebuggable = true
+            
+            // Optionales separates Icon-Label für Debug-Builds
+            resValue("string", "app_name_debug", "Simple Notes (Debug)")
+        }
+        
         release {
             isMinifyEnabled = true
             isShrinkResources = true
@@ -124,6 +135,9 @@ dependencies {
     // LocalBroadcastManager für UI Refresh
     implementation("androidx.localbroadcastmanager:localbroadcastmanager:1.1.0")
 
+    // SwipeRefreshLayout für Pull-to-Refresh
+    implementation("androidx.swiperefreshlayout:swiperefreshlayout:1.1.0")
+
     // Testing (bleiben so)
     testImplementation(libs.junit)
     androidTestImplementation(libs.androidx.junit)
@@ -134,4 +148,28 @@ dependencies {
 fun getBuildDate(): String {
     val dateFormat = SimpleDateFormat("yyyy-MM-dd", Locale.US)
     return dateFormat.format(Date())
+}
+
+// ⚡ v1.3.1: ktlint deaktiviert wegen Parser-Problemen
+// Aktivieren in v1.4.0 wenn Code-Stil bereinigt wurde
+// ktlint {
+//     android = true
+//     outputToConsole = true
+//     ignoreFailures = true
+//     enableExperimentalRules = false
+//     filter {
+//         exclude("**/generated/**")
+//         exclude("**/build/**")
+//     }
+// }
+
+// ⚡ v1.3.1: detekt-Konfiguration
+detekt {
+    buildUponDefaultConfig = true
+    allRules = false
+    config.setFrom(files("$rootDir/config/detekt/detekt.yml"))
+    baseline = file("$rootDir/config/detekt/baseline.xml")
+    
+    // Parallel-Verarbeitung für schnellere Checks
+    parallel = true
 }

android/app/src/main/AndroidManifest.xml

@@ -27,7 +27,7 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.SimpleNotes"
-        android:usesCleartextTraffic="true"
+        android:networkSecurityConfig="@xml/network_security_config"
         tools:targetApi="31">
         <activity
             android:name=".MainActivity"

android/app/src/main/java/dev/dettmer/simplenotes/MainActivity.kt

@@ -21,19 +21,29 @@ import com.google.android.material.color.DynamicColors
 import com.google.android.material.floatingactionbutton.FloatingActionButton
 import com.google.android.material.snackbar.Snackbar
 import com.google.android.material.card.MaterialCardView
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import dev.dettmer.simplenotes.adapters.NotesAdapter
+import dev.dettmer.simplenotes.models.Note
 import dev.dettmer.simplenotes.storage.NotesStorage
 import dev.dettmer.simplenotes.sync.SyncWorker
 import dev.dettmer.simplenotes.utils.NotificationHelper
 import dev.dettmer.simplenotes.utils.showToast
 import dev.dettmer.simplenotes.utils.Constants
 import android.widget.TextView
+import android.widget.CheckBox
+import android.widget.Toast
+import androidx.lifecycle.lifecycleScope
+import kotlinx.coroutines.launch
 import androidx.lifecycle.lifecycleScope
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import dev.dettmer.simplenotes.sync.WebDavSyncService
+import dev.dettmer.simplenotes.sync.SyncStateManager
 import androidx.core.splashscreen.SplashScreen.Companion.installSplashScreen
+import androidx.swiperefreshlayout.widget.SwipeRefreshLayout
+import android.view.View
+import android.widget.LinearLayout
 
 class MainActivity : AppCompatActivity() {
     
@@ -41,10 +51,21 @@ class MainActivity : AppCompatActivity() {
     private lateinit var emptyStateCard: MaterialCardView
     private lateinit var fabAddNote: FloatingActionButton
     private lateinit var toolbar: MaterialToolbar
+    private lateinit var swipeRefreshLayout: SwipeRefreshLayout
+    
+    // 🔄 v1.3.1: Sync Status Banner
+    private lateinit var syncStatusBanner: LinearLayout
+    private lateinit var syncStatusText: TextView
     
     private lateinit var adapter: NotesAdapter
     private val storage by lazy { NotesStorage(this) }
     
+    // Menu reference for sync button state
+    private var optionsMenu: Menu? = null
+    
+    // Track pending deletions to prevent flicker when notes reload
+    private val pendingDeletions = mutableSetOf<String>()
+    
     private val prefs by lazy {
         getSharedPreferences(Constants.PREFS_NAME, Context.MODE_PRIVATE)
     }
@@ -55,6 +76,8 @@ class MainActivity : AppCompatActivity() {
         private const val REQUEST_SETTINGS = 1002
         private const val MIN_AUTO_SYNC_INTERVAL_MS = 60_000L // 1 Minute
         private const val PREF_LAST_AUTO_SYNC_TIME = "last_auto_sync_timestamp"
+        private const val SYNC_COMPLETED_DELAY_MS = 1500L
+        private const val ERROR_DISPLAY_DELAY_MS = 3000L
     }
     
     /**
@@ -86,11 +109,15 @@ class MainActivity : AppCompatActivity() {
         
         setContentView(R.layout.activity_main)
         
-        // File Logging aktivieren wenn eingestellt
+        // Logger initialisieren und File-Logging aktivieren wenn eingestellt
-        if (prefs.getBoolean("file_logging_enabled", false)) {
+        Logger.init(this)
-            Logger.enableFileLogging(this)
+        if (prefs.getBoolean(Constants.KEY_FILE_LOGGING_ENABLED, false)) {
+            Logger.setFileLoggingEnabled(true)
         }
         
+        // Alte Sync-Notifications beim App-Start löschen
+        NotificationHelper.clearSyncNotifications(this)
+        
         // Permission für Notifications (Android 13+)
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
             requestNotificationPermission()
@@ -102,6 +129,65 @@ class MainActivity : AppCompatActivity() {
         setupFab()
         
         loadNotes()
+        
+        // 🔄 v1.3.1: Observe sync state for UI updates
+        setupSyncStateObserver()
+    }
+    
+    /**
+     * 🔄 v1.3.1: Beobachtet Sync-Status für UI-Feedback
+     */
+    private fun setupSyncStateObserver() {
+        SyncStateManager.syncStatus.observe(this) { status ->
+            when (status.state) {
+                SyncStateManager.SyncState.SYNCING -> {
+                    // Disable sync controls
+                    setSyncControlsEnabled(false)
+                    // 🔄 v1.3.1: Show sync status banner (ersetzt SwipeRefresh-Animation)
+                    syncStatusText.text = getString(R.string.sync_status_syncing)
+                    syncStatusBanner.visibility = View.VISIBLE
+                }
+                SyncStateManager.SyncState.COMPLETED -> {
+                    // Re-enable sync controls
+                    setSyncControlsEnabled(true)
+                    swipeRefreshLayout.isRefreshing = false
+                    // Show completed briefly, then hide
+                    syncStatusText.text = status.message ?: getString(R.string.sync_status_completed)
+                    lifecycleScope.launch {
+                        kotlinx.coroutines.delay(SYNC_COMPLETED_DELAY_MS)
+                        syncStatusBanner.visibility = View.GONE
+                        SyncStateManager.reset()
+                    }
+                }
+                SyncStateManager.SyncState.ERROR -> {
+                    // Re-enable sync controls
+                    setSyncControlsEnabled(true)
+                    swipeRefreshLayout.isRefreshing = false
+                    // Show error briefly, then hide
+                    syncStatusText.text = status.message ?: getString(R.string.sync_status_error)
+                    lifecycleScope.launch {
+                        kotlinx.coroutines.delay(ERROR_DISPLAY_DELAY_MS)
+                        syncStatusBanner.visibility = View.GONE
+                        SyncStateManager.reset()
+                    }
+                }
+                SyncStateManager.SyncState.IDLE -> {
+                    setSyncControlsEnabled(true)
+                    swipeRefreshLayout.isRefreshing = false
+                    syncStatusBanner.visibility = View.GONE
+                }
+            }
+        }
+    }
+    
+    /**
+     * 🔄 v1.3.1: Aktiviert/deaktiviert Sync-Controls (Button + SwipeRefresh)
+     */
+    private fun setSyncControlsEnabled(enabled: Boolean) {
+        // Menu Sync-Button
+        optionsMenu?.findItem(R.id.action_sync)?.isEnabled = enabled
+        // SwipeRefresh
+        swipeRefreshLayout.isEnabled = enabled
     }
     
     override fun onResume() {
@@ -117,7 +203,7 @@ class MainActivity : AppCompatActivity() {
         
         Logger.d(TAG, "📡 BroadcastReceiver registered (sync-completed)")
         
-        // Reload notes
+        // Reload notes (scroll to top wird in loadNotes() gemacht)
         loadNotes()
         
         // Trigger Auto-Sync beim App-Wechsel in Vordergrund (Toast)
@@ -137,15 +223,40 @@ class MainActivity : AppCompatActivity() {
             return
         }
         
+        // 🔄 v1.3.1: Check if sync already running
+        if (!SyncStateManager.tryStartSync("auto-$source")) {
+            Logger.d(TAG, "⏭️ Auto-sync ($source): Another sync already in progress")
+            return
+        }
+        
         Logger.d(TAG, "🔄 Auto-sync triggered ($source)")
         
         // Update last sync timestamp
         prefs.edit().putLong(PREF_LAST_AUTO_SYNC_TIME, System.currentTimeMillis()).apply()
         
-        // GLEICHER Sync-Code wie manueller Sync (funktioniert!)
         lifecycleScope.launch {
             try {
                 val syncService = WebDavSyncService(this@MainActivity)
+                
+                // 🔥 v1.1.2: Check if there are unsynced changes first (performance optimization)
+                if (!syncService.hasUnsyncedChanges()) {
+                    Logger.d(TAG, "⏭️ Auto-sync ($source): No unsynced changes - skipping")
+                    SyncStateManager.reset()
+                    return@launch
+                }
+                
+                // ⭐ WICHTIG: Server-Erreichbarkeits-Check VOR Sync (wie in SyncWorker)
+                val isReachable = withContext(Dispatchers.IO) {
+                    syncService.isServerReachable()
+                }
+                
+                if (!isReachable) {
+                    Logger.d(TAG, "⏭️ Auto-sync ($source): Server not reachable - skipping silently")
+                    SyncStateManager.reset()
+                    return@launch
+                }
+                
+                // Server ist erreichbar → Sync durchführen
                 val result = withContext(Dispatchers.IO) {
                     syncService.syncNotes()
                 }
@@ -153,6 +264,7 @@ class MainActivity : AppCompatActivity() {
                 // Feedback abhängig von Source
                 if (result.isSuccess && result.syncedCount > 0) {
                     Logger.d(TAG, "✅ Auto-sync successful ($source): ${result.syncedCount} notes")
+                    SyncStateManager.markCompleted("${result.syncedCount} Notizen")
                     
                     // onResume: Nur Success-Toast
                     showToast("✅ Gesynct: ${result.syncedCount} Notizen")
@@ -160,14 +272,17 @@ class MainActivity : AppCompatActivity() {
                     
                 } else if (result.isSuccess) {
                     Logger.d(TAG, "ℹ️ Auto-sync ($source): No changes")
+                    SyncStateManager.markCompleted()
                     
                 } else {
                     Logger.e(TAG, "❌ Auto-sync failed ($source): ${result.errorMessage}")
+                    SyncStateManager.markError(result.errorMessage)
                     // Kein Toast - App ist im Hintergrund
                 }
                 
             } catch (e: Exception) {
                 Logger.e(TAG, "💥 Auto-sync exception ($source): ${e.message}")
+                SyncStateManager.markError(e.message)
                 // Kein Toast - App ist im Hintergrund
             }
         }
@@ -203,6 +318,11 @@ class MainActivity : AppCompatActivity() {
         emptyStateCard = findViewById(R.id.emptyStateCard)
         fabAddNote = findViewById(R.id.fabAddNote)
         toolbar = findViewById(R.id.toolbar)
+        swipeRefreshLayout = findViewById<SwipeRefreshLayout>(R.id.swipeRefreshLayout)
+        
+        // 🔄 v1.3.1: Sync Status Banner
+        syncStatusBanner = findViewById(R.id.syncStatusBanner)
+        syncStatusText = findViewById(R.id.syncStatusText)
     }
     
     private fun setupToolbar() {
@@ -216,10 +336,74 @@ class MainActivity : AppCompatActivity() {
         recyclerViewNotes.adapter = adapter
         recyclerViewNotes.layoutManager = LinearLayoutManager(this)
         
+        // 🔥 v1.1.2: Setup Pull-to-Refresh
+        setupPullToRefresh()
+        
         // Setup Swipe-to-Delete
         setupSwipeToDelete()
     }
     
+    /**
+     * Setup Pull-to-Refresh für manuellen Sync (v1.1.2)
+     */
+    private fun setupPullToRefresh() {
+        swipeRefreshLayout.setOnRefreshListener {
+            Logger.d(TAG, "🔄 Pull-to-Refresh triggered - starting manual sync")
+            
+            // 🔄 v1.3.1: Check if sync already running (Banner zeigt Status)
+            if (!SyncStateManager.tryStartSync("pullToRefresh")) {
+                swipeRefreshLayout.isRefreshing = false
+                return@setOnRefreshListener
+            }
+            
+            lifecycleScope.launch {
+                try {
+                    val prefs = getSharedPreferences(Constants.PREFS_NAME, Context.MODE_PRIVATE)
+                    val serverUrl = prefs.getString(Constants.KEY_SERVER_URL, null)
+                    
+                    if (serverUrl.isNullOrEmpty()) {
+                        showToast("⚠️ Server noch nicht konfiguriert")
+                        SyncStateManager.reset()
+                        return@launch
+                    }
+                    
+                    val syncService = WebDavSyncService(this@MainActivity)
+                    
+                    // 🔥 v1.1.2: Check if there are unsynced changes first (performance optimization)
+                    if (!syncService.hasUnsyncedChanges()) {
+                        Logger.d(TAG, "⏭️ No unsynced changes, skipping server reachability check")
+                        SyncStateManager.markCompleted("Bereits synchronisiert")
+                        return@launch
+                    }
+                    
+                    // Check if server is reachable
+                    if (!syncService.isServerReachable()) {
+                        SyncStateManager.markError("Server nicht erreichbar")
+                        return@launch
+                    }
+                    
+                    // Perform sync
+                    val result = syncService.syncNotes()
+                    
+                    if (result.isSuccess) {
+                        SyncStateManager.markCompleted("${result.syncedCount} Notizen")
+                        loadNotes()
+                    } else {
+                        SyncStateManager.markError(result.errorMessage)
+                    }
+                } catch (e: Exception) {
+                    Logger.e(TAG, "Pull-to-Refresh sync failed", e)
+                    SyncStateManager.markError(e.message)
+                }
+            }
+        }
+        
+        // Set Material 3 color scheme
+        swipeRefreshLayout.setColorSchemeResources(
+            com.google.android.material.R.color.material_dynamic_primary50
+        )
+    }
+    
     private fun setupSwipeToDelete() {
         val itemTouchHelper = ItemTouchHelper(object : ItemTouchHelper.SimpleCallback(
             0, // No drag
@@ -232,31 +416,20 @@ class MainActivity : AppCompatActivity() {
             ): Boolean = false
             
             override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
-                val position = viewHolder.adapterPosition
+                val position = viewHolder.bindingAdapterPosition
-                val note = adapter.currentList[position]
+                val swipedNote = adapter.currentList[position]
-                val notesCopy = adapter.currentList.toMutableList()
                 
-                // Remove from list immediately for visual feedback
+                // Store original list BEFORE removing note
-                notesCopy.removeAt(position)
+                val originalList = adapter.currentList.toList()
-                adapter.submitList(notesCopy)
                 
-                // Show Snackbar with UNDO
+                // Remove from list for visual feedback (NOT from storage yet!)
-                Snackbar.make(
+                val listWithoutNote = originalList.toMutableList().apply {
-                    recyclerViewNotes,
+                    removeAt(position)
-                    "Notiz gelöscht",
+                }
-                    Snackbar.LENGTH_LONG
+                adapter.submitList(listWithoutNote)
-                ).setAction("RÜCKGÄNGIG") {
+                
-                    // UNDO: Restore note in list
+                // Show dialog with ability to restore
-                    loadNotes()
+                showServerDeletionDialog(swipedNote, originalList)
-                }.addCallback(object : Snackbar.Callback() {
-                    override fun onDismissed(transientBottomBar: Snackbar?, event: Int) {
-                        if (event != DISMISS_EVENT_ACTION) {
-                            // Snackbar dismissed without UNDO → Actually delete the note
-                            storage.deleteNote(note.id)
-                            loadNotes()
-                        }
-                    }
-                }).show()
             }
             
             override fun getSwipeThreshold(viewHolder: RecyclerView.ViewHolder): Float {
@@ -268,6 +441,116 @@ class MainActivity : AppCompatActivity() {
         itemTouchHelper.attachToRecyclerView(recyclerViewNotes)
     }
     
+    private fun showServerDeletionDialog(note: Note, originalList: List<Note>) {
+        val alwaysDeleteFromServer = prefs.getBoolean(Constants.KEY_ALWAYS_DELETE_FROM_SERVER, false)
+        
+        if (alwaysDeleteFromServer) {
+            // Auto-delete from server without asking
+            deleteNoteLocally(note, deleteFromServer = true)
+            return
+        }
+        
+        val dialogView = layoutInflater.inflate(R.layout.dialog_server_deletion, null)
+        val checkboxAlways = dialogView.findViewById<CheckBox>(R.id.checkboxAlwaysDeleteFromServer)
+        
+        MaterialAlertDialogBuilder(this)
+            .setTitle("Notiz löschen")
+            .setMessage("\"${note.title}\" wird lokal gelöscht.\n\nAuch vom Server löschen?")
+            .setView(dialogView)
+            .setNeutralButton("Abbrechen") { _, _ ->
+                // RESTORE: Re-submit original list (note is NOT deleted from storage)
+                adapter.submitList(originalList)
+            }
+            .setOnCancelListener {
+                // User pressed back - also restore
+                adapter.submitList(originalList)
+            }
+            .setPositiveButton("Nur lokal") { _, _ ->
+                if (checkboxAlways.isChecked) {
+                    prefs.edit().putBoolean(Constants.KEY_ALWAYS_DELETE_FROM_SERVER, false).apply()
+                }
+                // NOW actually delete from storage
+                deleteNoteLocally(note, deleteFromServer = false)
+            }
+            .setNegativeButton("Vom Server löschen") { _, _ ->
+                if (checkboxAlways.isChecked) {
+                    prefs.edit().putBoolean(Constants.KEY_ALWAYS_DELETE_FROM_SERVER, true).apply()
+                }
+                deleteNoteLocally(note, deleteFromServer = true)
+            }
+            .setCancelable(true)
+            .show()
+    }
+    
+    private fun deleteNoteLocally(note: Note, deleteFromServer: Boolean) {
+        // Track pending deletion to prevent flicker
+        pendingDeletions.add(note.id)
+        
+        // Delete from storage
+        storage.deleteNote(note.id)
+        
+        // Reload to reflect changes
+        loadNotes()
+        
+        // Show Snackbar with UNDO option
+        val message = if (deleteFromServer) {
+            "\"${note.title}\" wird lokal und vom Server gelöscht"
+        } else {
+            "\"${note.title}\" lokal gelöscht (Server bleibt)"
+        }
+        
+        Snackbar.make(recyclerViewNotes, message, Snackbar.LENGTH_LONG)
+            .setAction("RÜCKGÄNGIG") {
+                // UNDO: Restore note
+                storage.saveNote(note)
+                pendingDeletions.remove(note.id)
+                loadNotes()
+            }
+            .addCallback(object : Snackbar.Callback() {
+                override fun onDismissed(transientBottomBar: Snackbar?, event: Int) {
+                    if (event != DISMISS_EVENT_ACTION) {
+                        // Snackbar dismissed without UNDO
+                        pendingDeletions.remove(note.id)
+                        
+                        // Delete from server if requested
+                        if (deleteFromServer) {
+                            lifecycleScope.launch {
+                                try {
+                                    val webdavService = WebDavSyncService(this@MainActivity)
+                                    val success = webdavService.deleteNoteFromServer(note.id)
+                                    if (success) {
+                                        runOnUiThread {
+                                            Toast.makeText(
+                                                this@MainActivity,
+                                                "Vom Server gelöscht",
+                                                Toast.LENGTH_SHORT
+                                            ).show()
+                                        }
+                                    } else {
+                                        runOnUiThread {
+                                            Toast.makeText(
+                                                this@MainActivity,
+                                                "Server-Löschung fehlgeschlagen",
+                                                Toast.LENGTH_LONG
+                                            ).show()
+                                        }
+                                    }
+                                } catch (e: Exception) {
+                                    runOnUiThread {
+                                        Toast.makeText(
+                                            this@MainActivity,
+                                            "Server-Fehler: ${e.message}",
+                                            Toast.LENGTH_LONG
+                                        ).show()
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }).show()
+    }
+    
     private fun setupFab() {
         fabAddNote.setOnClickListener {
             openNoteEditor(null)
@@ -276,10 +559,21 @@ class MainActivity : AppCompatActivity() {
     
     private fun loadNotes() {
         val notes = storage.loadAllNotes()
-        adapter.submitList(notes)
+        
+        // Filter out notes that are pending deletion (prevent flicker)
+        val filteredNotes = notes.filter { it.id !in pendingDeletions }
+        
+        // Submit list with callback to scroll to top after list is updated
+        adapter.submitList(filteredNotes) {
+            // Scroll to top after list update is complete
+            // Wichtig: Nach dem Erstellen/Bearbeiten einer Notiz
+            if (filteredNotes.isNotEmpty()) {
+                recyclerViewNotes.scrollToPosition(0)
+            }
+        }
         
         // Material 3 Empty State Card
-        emptyStateCard.visibility = if (notes.isEmpty()) {
+        emptyStateCard.visibility = if (filteredNotes.isEmpty()) {
             android.view.View.VISIBLE
         } else {
             android.view.View.GONE
@@ -301,32 +595,56 @@ class MainActivity : AppCompatActivity() {
     }
     
     private fun triggerManualSync() {
+        // 🔄 v1.3.1: Check if sync already running (Banner zeigt Status)
+        if (!SyncStateManager.tryStartSync("manual")) {
+            return
+        }
+        
         lifecycleScope.launch {
             try {
-                showToast("Starte Synchronisation...")
+                // Create sync service
-                
-                // Start sync
                 val syncService = WebDavSyncService(this@MainActivity)
+                
+                // 🔥 v1.1.2: Check if there are unsynced changes first (performance optimization)
+                if (!syncService.hasUnsyncedChanges()) {
+                    Logger.d(TAG, "⏭️ Manual Sync: No unsynced changes - skipping")
+                    SyncStateManager.markCompleted("Bereits synchronisiert")
+                    return@launch
+                }
+                
+                // ⭐ WICHTIG: Server-Erreichbarkeits-Check VOR Sync (wie in SyncWorker)
+                val isReachable = withContext(Dispatchers.IO) {
+                    syncService.isServerReachable()
+                }
+                
+                if (!isReachable) {
+                    Logger.d(TAG, "⏭️ Manual Sync: Server not reachable - aborting")
+                    SyncStateManager.markError("Server nicht erreichbar")
+                    return@launch
+                }
+                
+                // Server ist erreichbar → Sync durchführen
                 val result = withContext(Dispatchers.IO) {
                     syncService.syncNotes()
                 }
                 
                 // Show result
                 if (result.isSuccess) {
-                    showToast("Sync erfolgreich: ${result.syncedCount} Notizen")
+                    SyncStateManager.markCompleted("${result.syncedCount} Notizen")
                     loadNotes() // Reload notes
                 } else {
-                    showToast("Sync Fehler: ${result.errorMessage}")
+                    SyncStateManager.markError(result.errorMessage)
                 }
                 
             } catch (e: Exception) {
-                showToast("Sync Fehler: ${e.message}")
+                SyncStateManager.markError(e.message)
             }
         }
     }
     
     override fun onCreateOptionsMenu(menu: Menu): Boolean {
         menuInflater.inflate(R.menu.menu_main, menu)
+        optionsMenu = menu  // 🔄 v1.3.1: Store reference for sync button state
         return true
     }
     
@@ -385,4 +703,4 @@ class MainActivity : AppCompatActivity() {
             }
         }
     }
-}
+}

android/app/src/main/java/dev/dettmer/simplenotes/NoteEditorActivity.kt

@@ -41,7 +41,8 @@ class NoteEditorActivity : AppCompatActivity() {
         setSupportActionBar(toolbar)
         supportActionBar?.apply {
             setDisplayHomeAsUpEnabled(true)
-            setHomeAsUpIndicator(android.R.drawable.ic_menu_close_clear_cancel)
+            // 🔥 v1.1.2: Use default back arrow (Material Design) instead of X icon
+            // Icon is set in XML: app:navigationIcon="?attr/homeAsUpIndicator"
         }
         
         // Find views

android/app/src/main/java/dev/dettmer/simplenotes/adapters/NotesAdapter.kt

@@ -1,5 +1,6 @@
 package dev.dettmer.simplenotes.adapters
 
+import android.content.Context
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
@@ -11,6 +12,7 @@ import androidx.recyclerview.widget.RecyclerView
 import dev.dettmer.simplenotes.R
 import dev.dettmer.simplenotes.models.Note
 import dev.dettmer.simplenotes.models.SyncStatus
+import dev.dettmer.simplenotes.utils.Constants
 import dev.dettmer.simplenotes.utils.toReadableTime
 import dev.dettmer.simplenotes.utils.truncate
 
@@ -39,14 +41,25 @@ class NotesAdapter(
             textViewContent.text = note.content.truncate(100)
             textViewTimestamp.text = note.updatedAt.toReadableTime()
             
-            // Sync status icon
+            // Sync Icon nur zeigen wenn Sync konfiguriert ist
-            val syncIcon = when (note.syncStatus) {
+            val prefs = itemView.context.getSharedPreferences(Constants.PREFS_NAME, Context.MODE_PRIVATE)
-                SyncStatus.SYNCED -> android.R.drawable.ic_menu_upload
+            val serverUrl = prefs.getString(Constants.KEY_SERVER_URL, null)
-                SyncStatus.PENDING -> android.R.drawable.ic_popup_sync
+            val isSyncConfigured = !serverUrl.isNullOrEmpty()
-                SyncStatus.CONFLICT -> android.R.drawable.ic_dialog_alert
+            
-                SyncStatus.LOCAL_ONLY -> android.R.drawable.ic_menu_save
+            if (isSyncConfigured) {
+                // Sync status icon
+                val syncIcon = when (note.syncStatus) {
+                    SyncStatus.SYNCED -> android.R.drawable.ic_menu_upload
+                    SyncStatus.PENDING -> android.R.drawable.ic_popup_sync
+                    SyncStatus.CONFLICT -> android.R.drawable.ic_dialog_alert
+                    SyncStatus.LOCAL_ONLY -> android.R.drawable.ic_menu_save
+                }
+                imageViewSyncStatus.setImageResource(syncIcon)
+                imageViewSyncStatus.visibility = View.VISIBLE
+            } else {
+                // Sync nicht konfiguriert → Icon verstecken
+                imageViewSyncStatus.visibility = View.GONE
             }
-            imageViewSyncStatus.setImageResource(syncIcon)
             
             itemView.setOnClickListener {
                 onNoteClick(note)

android/app/src/main/java/dev/dettmer/simplenotes/backup/BackupManager.kt

@@ -0,0 +1,367 @@
+package dev.dettmer.simplenotes.backup
+
+import android.content.Context
+import android.net.Uri
+import com.google.gson.Gson
+import com.google.gson.GsonBuilder
+import dev.dettmer.simplenotes.BuildConfig
+import dev.dettmer.simplenotes.models.Note
+import dev.dettmer.simplenotes.storage.NotesStorage
+import dev.dettmer.simplenotes.utils.Logger
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import java.io.File
+import java.text.SimpleDateFormat
+import java.util.*
+
+/**
+ * BackupManager: Lokale Backup & Restore Funktionalität
+ * 
+ * Features:
+ * - Backup aller Notizen in JSON-Datei
+ * - Restore mit 3 Modi (Merge, Replace, Overwrite Duplicates)
+ * - Auto-Backup vor Restore (Sicherheitsnetz)
+ * - Backup-Validierung
+ */
+class BackupManager(private val context: Context) {
+    
+    companion object {
+        private const val TAG = "BackupManager"
+        private const val BACKUP_VERSION = 1
+        private const val AUTO_BACKUP_DIR = "auto_backups"
+        private const val AUTO_BACKUP_RETENTION_DAYS = 7
+    }
+    
+    private val storage = NotesStorage(context)
+    private val gson: Gson = GsonBuilder().setPrettyPrinting().create()
+    
+    /**
+     * Erstellt Backup aller Notizen
+     * 
+     * @param uri Output-URI (via Storage Access Framework)
+     * @return BackupResult mit Erfolg/Fehler Info
+     */
+    suspend fun createBackup(uri: Uri): BackupResult = withContext(Dispatchers.IO) {
+        return@withContext try {
+            Logger.d(TAG, "📦 Creating backup to: $uri")
+            
+            val allNotes = storage.loadAllNotes()
+            Logger.d(TAG, "   Found ${allNotes.size} notes to backup")
+            
+            val backupData = BackupData(
+                backupVersion = BACKUP_VERSION,
+                createdAt = System.currentTimeMillis(),
+                notesCount = allNotes.size,
+                appVersion = BuildConfig.VERSION_NAME,
+                notes = allNotes
+            )
+            
+            val jsonString = gson.toJson(backupData)
+            
+            context.contentResolver.openOutputStream(uri)?.use { outputStream ->
+                outputStream.write(jsonString.toByteArray())
+                Logger.d(TAG, "✅ Backup created successfully")
+            }
+            
+            BackupResult(
+                success = true,
+                notesCount = allNotes.size,
+                message = "Backup erstellt: ${allNotes.size} Notizen"
+            )
+            
+        } catch (e: Exception) {
+            Logger.e(TAG, "Failed to create backup", e)
+            BackupResult(
+                success = false,
+                error = "Backup fehlgeschlagen: ${e.message}"
+            )
+        }
+    }
+    
+    /**
+     * Erstellt automatisches Backup (vor Restore)
+     * Gespeichert in app-internem Storage
+     * 
+     * @return Uri des Auto-Backups oder null bei Fehler
+     */
+    suspend fun createAutoBackup(): Uri? = withContext(Dispatchers.IO) {
+        return@withContext try {
+            val autoBackupDir = File(context.filesDir, AUTO_BACKUP_DIR).apply {
+                if (!exists()) mkdirs()
+            }
+            
+            val timestamp = SimpleDateFormat("yyyy-MM-dd_HHmmss", Locale.US)
+                .format(Date())
+            val filename = "auto_backup_before_restore_$timestamp.json"
+            val file = File(autoBackupDir, filename)
+            
+            Logger.d(TAG, "📦 Creating auto-backup: ${file.absolutePath}")
+            
+            val allNotes = storage.loadAllNotes()
+            val backupData = BackupData(
+                backupVersion = BACKUP_VERSION,
+                createdAt = System.currentTimeMillis(),
+                notesCount = allNotes.size,
+                appVersion = BuildConfig.VERSION_NAME,
+                notes = allNotes
+            )
+            
+            file.writeText(gson.toJson(backupData))
+            
+            // Cleanup alte Auto-Backups
+            cleanupOldAutoBackups(autoBackupDir)
+            
+            Logger.d(TAG, "✅ Auto-backup created: ${file.absolutePath}")
+            Uri.fromFile(file)
+            
+        } catch (e: Exception) {
+            Logger.e(TAG, "Failed to create auto-backup", e)
+            null
+        }
+    }
+    
+    /**
+     * Stellt Notizen aus Backup wieder her
+     * 
+     * @param uri Backup-Datei URI
+     * @param mode Wiederherstellungs-Modus (Merge/Replace/Overwrite)
+     * @return RestoreResult mit Details
+     */
+    suspend fun restoreBackup(uri: Uri, mode: RestoreMode): RestoreResult = withContext(Dispatchers.IO) {
+        return@withContext try {
+            Logger.d(TAG, "📥 Restoring backup from: $uri (mode: $mode)")
+            
+            // 1. Backup-Datei lesen
+            val jsonString = context.contentResolver.openInputStream(uri)?.use { inputStream ->
+                inputStream.bufferedReader().use { it.readText() }
+            } ?: return@withContext RestoreResult(
+                success = false,
+                error = "Datei konnte nicht gelesen werden"
+            )
+            
+            // 2. Backup validieren & parsen
+            val validationResult = validateBackup(jsonString)
+            if (!validationResult.isValid) {
+                return@withContext RestoreResult(
+                    success = false,
+                    error = validationResult.errorMessage ?: "Ungültige Backup-Datei"
+                )
+            }
+            
+            val backupData = gson.fromJson(jsonString, BackupData::class.java)
+            Logger.d(TAG, "   Backup valid: ${backupData.notesCount} notes, version ${backupData.backupVersion}")
+            
+            // 3. Auto-Backup erstellen (Sicherheitsnetz)
+            val autoBackupUri = createAutoBackup()
+            if (autoBackupUri == null) {
+                Logger.w(TAG, "⚠️ Auto-backup failed, but continuing with restore")
+            }
+            
+            // 4. Restore durchführen (je nach Modus)
+            val result = when (mode) {
+                RestoreMode.MERGE -> restoreMerge(backupData.notes)
+                RestoreMode.REPLACE -> restoreReplace(backupData.notes)
+                RestoreMode.OVERWRITE_DUPLICATES -> restoreOverwriteDuplicates(backupData.notes)
+            }
+            
+            Logger.d(TAG, "✅ Restore completed: ${result.importedNotes} imported, ${result.skippedNotes} skipped")
+            result
+            
+        } catch (e: Exception) {
+            Logger.e(TAG, "Failed to restore backup", e)
+            RestoreResult(
+                success = false,
+                error = "Wiederherstellung fehlgeschlagen: ${e.message}"
+            )
+        }
+    }
+    
+    /**
+     * Validiert Backup-Datei
+     */
+    private fun validateBackup(jsonString: String): ValidationResult {
+        return try {
+            val backupData = gson.fromJson(jsonString, BackupData::class.java)
+            
+            // Version kompatibel?
+            if (backupData.backupVersion > BACKUP_VERSION) {
+                return ValidationResult(
+                    isValid = false,
+                    errorMessage = "Backup-Version nicht unterstützt " +
+                        "(v${backupData.backupVersion} benötigt v${BACKUP_VERSION}+)"
+                )
+            }
+            
+            // Notizen-Array vorhanden?
+            if (backupData.notes.isEmpty()) {
+                return ValidationResult(
+                    isValid = false,
+                    errorMessage = "Backup enthält keine Notizen"
+                )
+            }
+            
+            // Alle Notizen haben ID, title, content?
+            val invalidNotes = backupData.notes.filter { note ->
+                note.id.isBlank() || note.title.isBlank()
+            }
+            
+            if (invalidNotes.isNotEmpty()) {
+                return ValidationResult(
+                    isValid = false,
+                    errorMessage = "Backup enthält ${invalidNotes.size} ungültige Notizen"
+                )
+            }
+            
+            ValidationResult(isValid = true)
+            
+        } catch (e: Exception) {
+            ValidationResult(
+                isValid = false,
+                errorMessage = "Backup-Datei beschädigt oder ungültig: ${e.message}"
+            )
+        }
+    }
+    
+    /**
+     * Restore-Modus: MERGE
+     * Fügt neue Notizen hinzu, behält bestehende
+     */
+    private fun restoreMerge(backupNotes: List<Note>): RestoreResult {
+        val existingNotes = storage.loadAllNotes()
+        val existingIds = existingNotes.map { it.id }.toSet()
+        
+        val newNotes = backupNotes.filter { it.id !in existingIds }
+        val skippedNotes = backupNotes.size - newNotes.size
+        
+        newNotes.forEach { note ->
+            storage.saveNote(note)
+        }
+        
+        return RestoreResult(
+            success = true,
+            importedNotes = newNotes.size,
+            skippedNotes = skippedNotes,
+            message = "${newNotes.size} neue Notizen importiert, $skippedNotes übersprungen"
+        )
+    }
+    
+    /**
+     * Restore-Modus: REPLACE
+     * Löscht alle bestehenden Notizen, importiert Backup
+     */
+    private fun restoreReplace(backupNotes: List<Note>): RestoreResult {
+        // Alle bestehenden Notizen löschen
+        storage.deleteAllNotes()
+        
+        // Backup-Notizen importieren
+        backupNotes.forEach { note ->
+            storage.saveNote(note)
+        }
+        
+        return RestoreResult(
+            success = true,
+            importedNotes = backupNotes.size,
+            skippedNotes = 0,
+            message = "Alle Notizen ersetzt: ${backupNotes.size} importiert"
+        )
+    }
+    
+    /**
+     * Restore-Modus: OVERWRITE_DUPLICATES
+     * Backup überschreibt bei ID-Konflikten
+     */
+    private fun restoreOverwriteDuplicates(backupNotes: List<Note>): RestoreResult {
+        val existingNotes = storage.loadAllNotes()
+        val existingIds = existingNotes.map { it.id }.toSet()
+        
+        val newNotes = backupNotes.filter { it.id !in existingIds }
+        val overwrittenNotes = backupNotes.filter { it.id in existingIds }
+        
+        // Alle Backup-Notizen speichern (überschreibt automatisch)
+        backupNotes.forEach { note ->
+            storage.saveNote(note)
+        }
+        
+        return RestoreResult(
+            success = true,
+            importedNotes = newNotes.size,
+            skippedNotes = 0,
+            overwrittenNotes = overwrittenNotes.size,
+            message = "${newNotes.size} neu, ${overwrittenNotes.size} überschrieben"
+        )
+    }
+    
+    /**
+     * Löscht Auto-Backups älter als RETENTION_DAYS
+     */
+    private fun cleanupOldAutoBackups(autoBackupDir: File) {
+        try {
+            val retentionTimeMs = AUTO_BACKUP_RETENTION_DAYS * 24 * 60 * 60 * 1000L
+            val cutoffTime = System.currentTimeMillis() - retentionTimeMs
+            
+            autoBackupDir.listFiles()?.forEach { file ->
+                if (file.lastModified() < cutoffTime) {
+                    Logger.d(TAG, "🗑️ Deleting old auto-backup: ${file.name}")
+                    file.delete()
+                }
+            }
+        } catch (e: Exception) {
+            Logger.e(TAG, "Failed to cleanup old backups", e)
+        }
+    }
+}
+
+/**
+ * Backup-Daten Struktur (JSON)
+ * NOTE: Property names use @SerializedName for JSON compatibility with snake_case
+ */
+data class BackupData(
+    @com.google.gson.annotations.SerializedName("backup_version")
+    val backupVersion: Int,
+    @com.google.gson.annotations.SerializedName("created_at")
+    val createdAt: Long,
+    @com.google.gson.annotations.SerializedName("notes_count")
+    val notesCount: Int,
+    @com.google.gson.annotations.SerializedName("app_version")
+    val appVersion: String,
+    val notes: List<Note>
+)
+
+/**
+ * Wiederherstellungs-Modi
+ */
+enum class RestoreMode {
+    MERGE,                  // Bestehende + Neue (Standard)
+    REPLACE,                // Alles löschen + Importieren
+    OVERWRITE_DUPLICATES    // Backup überschreibt bei ID-Konflikten
+}
+
+/**
+ * Backup-Ergebnis
+ */
+data class BackupResult(
+    val success: Boolean,
+    val notesCount: Int = 0,
+    val message: String? = null,
+    val error: String? = null
+)
+
+/**
+ * Restore-Ergebnis
+ */
+data class RestoreResult(
+    val success: Boolean,
+    val importedNotes: Int = 0,
+    val skippedNotes: Int = 0,
+    val overwrittenNotes: Int = 0,
+    val message: String? = null,
+    val error: String? = null
+)
+
+/**
+ * Validierungs-Ergebnis
+ */
+data class ValidationResult(
+    val isValid: Boolean,
+    val errorMessage: String? = null
+)

android/app/src/main/java/dev/dettmer/simplenotes/models/DeletionTracker.kt

@@ -0,0 +1,81 @@
+package dev.dettmer.simplenotes.models
+
+import dev.dettmer.simplenotes.utils.Logger
+import org.json.JSONArray
+import org.json.JSONObject
+
+data class DeletionRecord(
+    val id: String,
+    val deletedAt: Long,
+    val deviceId: String
+)
+
+data class DeletionTracker(
+    val version: Int = 1,
+    val deletedNotes: MutableList<DeletionRecord> = mutableListOf()
+) {
+    fun addDeletion(noteId: String, deviceId: String) {
+        if (!deletedNotes.any { it.id == noteId }) {
+            deletedNotes.add(DeletionRecord(noteId, System.currentTimeMillis(), deviceId))
+        }
+    }
+    
+    fun isDeleted(noteId: String): Boolean {
+        return deletedNotes.any { it.id == noteId }
+    }
+    
+    fun getDeletionTimestamp(noteId: String): Long? {
+        return deletedNotes.find { it.id == noteId }?.deletedAt
+    }
+    
+    fun removeDeletion(noteId: String) {
+        deletedNotes.removeIf { it.id == noteId }
+    }
+    
+    fun toJson(): String {
+        val jsonObject = JSONObject()
+        jsonObject.put("version", version)
+        
+        val notesArray = JSONArray()
+        for (record in deletedNotes) {
+            val recordObj = JSONObject()
+            recordObj.put("id", record.id)
+            recordObj.put("deletedAt", record.deletedAt)
+            recordObj.put("deviceId", record.deviceId)
+            notesArray.put(recordObj)
+        }
+        jsonObject.put("deletedNotes", notesArray)
+        
+        return jsonObject.toString(2)  // Pretty print with 2-space indent
+    }
+    
+    companion object {
+        private const val TAG = "DeletionTracker"
+        
+        fun fromJson(json: String): DeletionTracker? {
+            return try {
+                val jsonObject = JSONObject(json)
+                val version = jsonObject.optInt("version", 1)
+                val deletedNotes = mutableListOf<DeletionRecord>()
+                
+                val notesArray = jsonObject.optJSONArray("deletedNotes")
+                if (notesArray != null) {
+                    for (i in 0 until notesArray.length()) {
+                        val recordObj = notesArray.getJSONObject(i)
+                        val record = DeletionRecord(
+                            id = recordObj.getString("id"),
+                            deletedAt = recordObj.getLong("deletedAt"),
+                            deviceId = recordObj.getString("deviceId")
+                        )
+                        deletedNotes.add(record)
+                    }
+                }
+                
+                DeletionTracker(version, deletedNotes)
+            } catch (e: Exception) {
+                Logger.w(TAG, "Failed to parse DeletionTracker JSON: ${e.message}")
+                null
+            }
+        }
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/models/Note.kt

@@ -1,5 +1,10 @@
 package dev.dettmer.simplenotes.models
 
+import dev.dettmer.simplenotes.utils.Logger
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+import java.util.TimeZone
 import java.util.UUID
 
 data class Note(
@@ -25,15 +30,111 @@ data class Note(
         """.trimIndent()
     }
     
+    /**
+     * Konvertiert Note zu Markdown mit YAML Frontmatter (Task #1.2.0-08)
+     * Format kompatibel mit Obsidian, Joplin, Typora
+     */
+    fun toMarkdown(): String {
+        return """
+---
+id: $id
+created: ${formatISO8601(createdAt)}
+updated: ${formatISO8601(updatedAt)}
+device: $deviceId
+---
+
+# $title
+
+$content
+        """.trimIndent()
+    }
+    
     companion object {
+        private const val TAG = "Note"
+        
         fun fromJson(json: String): Note? {
             return try {
                 val gson = com.google.gson.Gson()
                 gson.fromJson(json, Note::class.java)
             } catch (e: Exception) {
+                Logger.w(TAG, "Failed to parse JSON: ${e.message}")
                 null
             }
         }
+        
+        /**
+         * Parst Markdown zurück zu Note-Objekt (Task #1.2.0-09)
+         * 
+         * @param md Markdown-String mit YAML Frontmatter
+         * @return Note-Objekt oder null bei Parse-Fehler
+         */
+        fun fromMarkdown(md: String): Note? {
+            return try {
+                // Parse YAML Frontmatter + Markdown Content
+                val frontmatterRegex = Regex("^---\\n(.+?)\\n---\\n(.*)$", RegexOption.DOT_MATCHES_ALL)
+                val match = frontmatterRegex.find(md) ?: return null
+                
+                val yamlBlock = match.groupValues[1]
+                val contentBlock = match.groupValues[2]
+                
+                // Parse YAML (einfach per String-Split für MVP)
+                val metadata = yamlBlock.lines()
+                    .mapNotNull { line ->
+                        val parts = line.split(":", limit = 2)
+                        if (parts.size == 2) {
+                            parts[0].trim() to parts[1].trim()
+                        } else null
+                    }.toMap()
+                
+                // Extract title from first # heading
+                val title = contentBlock.lines()
+                    .firstOrNull { it.startsWith("# ") }
+                    ?.removePrefix("# ")?.trim() ?: "Untitled"
+                
+                // Extract content (everything after heading)
+                val content = contentBlock
+                    .substringAfter("# $title\n\n", "")
+                    .trim()
+                
+                Note(
+                    id = metadata["id"] ?: UUID.randomUUID().toString(),
+                    title = title,
+                    content = content,
+                    createdAt = parseISO8601(metadata["created"] ?: ""),
+                    updatedAt = parseISO8601(metadata["updated"] ?: ""),
+                    deviceId = metadata["device"] ?: "desktop",
+                    syncStatus = SyncStatus.SYNCED  // Annahme: Vom Server importiert
+                )
+            } catch (e: Exception) {
+                Logger.w(TAG, "Failed to parse Markdown: ${e.message}")
+                null
+            }
+        }
+        
+        /**
+         * Formatiert Timestamp zu ISO8601 (Task #1.2.0-10)
+         * Format: 2024-12-21T18:00:00Z (UTC)
+         */
+        private fun formatISO8601(timestamp: Long): String {
+            val sdf = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'", Locale.US)
+            sdf.timeZone = TimeZone.getTimeZone("UTC")
+            return sdf.format(Date(timestamp))
+        }
+        
+        /**
+         * Parst ISO8601 zurück zu Timestamp (Task #1.2.0-10)
+         * Fallback: Aktueller Timestamp bei Fehler
+         */
+        private fun parseISO8601(dateString: String): Long {
+            return try {
+                val sdf = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'", Locale.US)
+                sdf.timeZone = TimeZone.getTimeZone("UTC")
+                sdf.parse(dateString)?.time ?: System.currentTimeMillis()
+            } catch (e: Exception) {
+                Logger.w(TAG, "Failed to parse ISO8601 date '$dateString': ${e.message}")
+                System.currentTimeMillis()  // Fallback
+            }
+        }
     }
 }
 

android/app/src/main/java/dev/dettmer/simplenotes/storage/NotesStorage.kt

@@ -1,11 +1,18 @@
 package dev.dettmer.simplenotes.storage
 
 import android.content.Context
+import dev.dettmer.simplenotes.models.DeletionTracker
 import dev.dettmer.simplenotes.models.Note
+import dev.dettmer.simplenotes.utils.DeviceIdGenerator
+import dev.dettmer.simplenotes.utils.Logger
 import java.io.File
 
 class NotesStorage(private val context: Context) {
     
+    companion object {
+        private const val TAG = "NotesStorage"
+    }
+    
     private val notesDir: File = File(context.filesDir, "notes").apply {
         if (!exists()) mkdirs()
     }
@@ -34,19 +41,89 @@ class NotesStorage(private val context: Context) {
     
     fun deleteNote(id: String): Boolean {
         val file = File(notesDir, "$id.json")
-        return file.delete()
+        val deleted = file.delete()
+        
+        if (deleted) {
+            Logger.d(TAG, "🗑️ Deleted note: $id")
+            
+            // Track deletion to prevent zombie notes
+            val deviceId = DeviceIdGenerator.getDeviceId(context)
+            trackDeletion(id, deviceId)
+        }
+        
+        return deleted
     }
     
     fun deleteAllNotes(): Boolean {
         return try {
-            notesDir.listFiles()
+            val notes = loadAllNotes()
-                ?.filter { it.extension == "json" }
+            val deviceId = DeviceIdGenerator.getDeviceId(context)
-                ?.forEach { it.delete() }
+            
+            for (note in notes) {
+                deleteNote(note.id)  // Uses trackDeletion() automatically
+            }
+            
+            Logger.d(TAG, "🗑️ Deleted all notes (${notes.size} notes)")
             true
         } catch (e: Exception) {
+            Logger.e(TAG, "Failed to delete all notes", e)
             false
         }
     }
     
+    // === Deletion Tracking ===
+    
+    private fun getDeletionTrackerFile(): File {
+        return File(context.filesDir, "deleted_notes.json")
+    }
+    
+    fun loadDeletionTracker(): DeletionTracker {
+        val file = getDeletionTrackerFile()
+        if (!file.exists()) {
+            return DeletionTracker()
+        }
+        
+        return try {
+            val json = file.readText()
+            DeletionTracker.fromJson(json) ?: DeletionTracker()
+        } catch (e: Exception) {
+            Logger.e(TAG, "Failed to load deletion tracker", e)
+            DeletionTracker()
+        }
+    }
+    
+    fun saveDeletionTracker(tracker: DeletionTracker) {
+        try {
+            val file = getDeletionTrackerFile()
+            file.writeText(tracker.toJson())
+            
+            if (tracker.deletedNotes.size > 1000) {
+                Logger.w(TAG, "⚠️ Deletion tracker large: ${tracker.deletedNotes.size} entries")
+            }
+            
+            Logger.d(TAG, "✅ Deletion tracker saved (${tracker.deletedNotes.size} entries)")
+        } catch (e: Exception) {
+            Logger.e(TAG, "Failed to save deletion tracker", e)
+        }
+    }
+    
+    fun trackDeletion(noteId: String, deviceId: String) {
+        val tracker = loadDeletionTracker()
+        tracker.addDeletion(noteId, deviceId)
+        saveDeletionTracker(tracker)
+        Logger.d(TAG, "📝 Tracked deletion: $noteId")
+    }
+    
+    fun isNoteDeleted(noteId: String): Boolean {
+        val tracker = loadDeletionTracker()
+        return tracker.isDeleted(noteId)
+    }
+    
+    fun clearDeletionTracker() {
+        saveDeletionTracker(DeletionTracker())
+        Logger.d(TAG, "🗑️ Deletion tracker cleared")
+    }
+
+    
     fun getNotesDir(): File = notesDir
 }

android/app/src/main/java/dev/dettmer/simplenotes/sync/NetworkMonitor.kt

@@ -227,7 +227,11 @@ class NetworkMonitor(private val context: Context) {
             if (isWifi) {
                 lastConnectedNetworkId = activeNetwork.toString()
                 Logger.d(TAG, "    ✅ Initial WiFi network: $lastConnectedNetworkId")
-                Logger.d(TAG, "    📡 WiFi already connected at startup - onAvailable() will only trigger on network change")
+                Logger.d(
+                    TAG,
+                    "    📡 WiFi already connected at startup - " +
+                        "onAvailable() will only trigger on network change"
+                )
             } else {
                 lastConnectedNetworkId = null
                 Logger.d(TAG, "    ⚠️ Not on WiFi at startup")
@@ -268,7 +272,7 @@ class NetworkMonitor(private val context: Context) {
             connectivityManager.unregisterNetworkCallback(networkCallback)
             Logger.d(TAG, "✅ WiFi monitoring stopped")
         } catch (e: Exception) {
-            // Already unregistered
+            Logger.w(TAG, "NetworkCallback already unregistered: ${e.message}")
         }
     }
 }

android/app/src/main/java/dev/dettmer/simplenotes/sync/SyncStateManager.kt

@@ -0,0 +1,129 @@
+package dev.dettmer.simplenotes.sync
+
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import dev.dettmer.simplenotes.utils.Logger
+
+/**
+ * 🔄 v1.3.1: Zentrale Verwaltung des Sync-Status
+ * 
+ * Verhindert doppelte Syncs und informiert die UI über den aktuellen Status.
+ * Thread-safe Singleton mit LiveData für UI-Reaktivität.
+ */
+object SyncStateManager {
+    
+    private const val TAG = "SyncStateManager"
+    
+    /**
+     * Mögliche Sync-Zustände
+     */
+    enum class SyncState {
+        IDLE,           // Kein Sync aktiv
+        SYNCING,        // Sync läuft gerade
+        COMPLETED,      // Sync erfolgreich abgeschlossen (kurz anzeigen)
+        ERROR           // Sync fehlgeschlagen (kurz anzeigen)
+    }
+    
+    /**
+     * Detaillierte Sync-Informationen für UI
+     */
+    data class SyncStatus(
+        val state: SyncState = SyncState.IDLE,
+        val message: String? = null,
+        val source: String? = null,  // "manual", "auto", "pullToRefresh", "background"
+        val timestamp: Long = System.currentTimeMillis()
+    )
+    
+    // Private mutable LiveData
+    private val _syncStatus = MutableLiveData(SyncStatus())
+    
+    // Public immutable LiveData für Observer
+    val syncStatus: LiveData<SyncStatus> = _syncStatus
+    
+    // Lock für Thread-Sicherheit
+    private val lock = Any()
+    
+    /**
+     * Prüft ob gerade ein Sync läuft
+     */
+    val isSyncing: Boolean
+        get() = _syncStatus.value?.state == SyncState.SYNCING
+    
+    /**
+     * Versucht einen Sync zu starten.
+     * @return true wenn Sync gestartet werden kann, false wenn bereits einer läuft
+     */
+    fun tryStartSync(source: String): Boolean {
+        synchronized(lock) {
+            if (isSyncing) {
+                Logger.d(TAG, "⚠️ Sync already in progress, rejecting new sync from: $source")
+                return false
+            }
+            
+            Logger.d(TAG, "🔄 Starting sync from: $source")
+            _syncStatus.postValue(
+                SyncStatus(
+                    state = SyncState.SYNCING,
+                    message = "Synchronisiere...",
+                    source = source
+                )
+            )
+            return true
+        }
+    }
+    
+    /**
+     * Markiert Sync als erfolgreich abgeschlossen
+     */
+    fun markCompleted(message: String? = null) {
+        synchronized(lock) {
+            val currentSource = _syncStatus.value?.source
+            Logger.d(TAG, "✅ Sync completed from: $currentSource")
+            _syncStatus.postValue(
+                SyncStatus(
+                    state = SyncState.COMPLETED,
+                    message = message,
+                    source = currentSource
+                )
+            )
+        }
+    }
+    
+    /**
+     * Markiert Sync als fehlgeschlagen
+     */
+    fun markError(errorMessage: String?) {
+        synchronized(lock) {
+            val currentSource = _syncStatus.value?.source
+            Logger.e(TAG, "❌ Sync failed from: $currentSource - $errorMessage")
+            _syncStatus.postValue(
+                SyncStatus(
+                    state = SyncState.ERROR,
+                    message = errorMessage,
+                    source = currentSource
+                )
+            )
+        }
+    }
+    
+    /**
+     * Setzt Status zurück auf IDLE
+     */
+    fun reset() {
+        synchronized(lock) {
+            _syncStatus.postValue(SyncStatus())
+        }
+    }
+    
+    /**
+     * Aktualisiert die Nachricht während des Syncs (z.B. Progress)
+     */
+    fun updateMessage(message: String) {
+        synchronized(lock) {
+            val current = _syncStatus.value ?: return
+            if (current.state == SyncState.SYNCING) {
+                _syncStatus.postValue(current.copy(message = message))
+            }
+        }
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/sync/SyncWorker.kt

@@ -8,6 +8,7 @@ import androidx.work.WorkerParameters
 import dev.dettmer.simplenotes.BuildConfig
 import dev.dettmer.simplenotes.utils.Logger
 import dev.dettmer.simplenotes.utils.NotificationHelper
+import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 
@@ -52,7 +53,49 @@ class SyncWorker(
             }
             
             if (BuildConfig.DEBUG) {
-                Logger.d(TAG, "📍 Step 2: Before syncNotes() call")
+                Logger.d(TAG, "📍 Step 2: Checking for unsynced changes (Performance Pre-Check)")
+            }
+            
+            // 🔥 v1.1.2: Performance-Optimierung - Skip Sync wenn keine lokalen Änderungen
+            // Spart Batterie + Netzwerk-Traffic + Server-Last
+            if (!syncService.hasUnsyncedChanges()) {
+                Logger.d(TAG, "⏭️ No local changes - skipping sync (performance optimization)")
+                Logger.d(TAG, "   Saves battery, network traffic, and server load")
+                
+                if (BuildConfig.DEBUG) {
+                    Logger.d(TAG, "✅ SyncWorker.doWork() SUCCESS (no changes to sync)")
+                    Logger.d(TAG, "═══════════════════════════════════════")
+                }
+                
+                return@withContext Result.success()
+            }
+            
+            if (BuildConfig.DEBUG) {
+                Logger.d(TAG, "📍 Step 3: Checking server reachability (Pre-Check)")
+            }
+            
+            // ⭐ KRITISCH: Server-Erreichbarkeits-Check VOR Sync
+            // Verhindert Fehler-Notifications in fremden WiFi-Netzen
+            // Wartet bis Netzwerk bereit ist (DHCP, Routing, Gateway)
+            if (!syncService.isServerReachable()) {
+                Logger.d(TAG, "⏭️ Server not reachable - skipping sync (no error)")
+                Logger.d(TAG, "   Reason: Server offline/wrong network/network not ready/not configured")
+                Logger.d(TAG, "   This is normal in foreign WiFi or during network initialization")
+                
+                // 🔥 v1.1.2: Check if we should show warning (server unreachable for >24h)
+                checkAndShowSyncWarning(syncService)
+                
+                if (BuildConfig.DEBUG) {
+                    Logger.d(TAG, "✅ SyncWorker.doWork() SUCCESS (silent skip)")
+                    Logger.d(TAG, "═══════════════════════════════════════")
+                }
+                
+                // Success zurückgeben (kein Fehler, Server ist halt nicht erreichbar)
+                return@withContext Result.success()
+            }
+            
+            if (BuildConfig.DEBUG) {
+                Logger.d(TAG, "📍 Step 3: Server reachable - proceeding with sync")
                 Logger.d(TAG, "    SyncService: $syncService")
             }
             
@@ -73,13 +116,17 @@ class SyncWorker(
             }
             
             if (BuildConfig.DEBUG) {
-                Logger.d(TAG, "📍 Step 3: Processing result")
+                Logger.d(TAG, "📍 Step 4: Processing result")
-                Logger.d(TAG, "📦 Sync result: success=${result.isSuccess}, count=${result.syncedCount}, error=${result.errorMessage}")
+                Logger.d(
+                    TAG,
+                    "📦 Sync result: success=${result.isSuccess}, " +
+                        "count=${result.syncedCount}, error=${result.errorMessage}"
+                )
             }
             
             if (result.isSuccess) {
                 if (BuildConfig.DEBUG) {
-                    Logger.d(TAG, "📍 Step 4: Success path")
+                    Logger.d(TAG, "📍 Step 5: Success path")
                 }
                 Logger.i(TAG, "✅ Sync successful: ${result.syncedCount} notes")
                 
@@ -109,7 +156,7 @@ class SyncWorker(
                 Result.success()
             } else {
                 if (BuildConfig.DEBUG) {
-                    Logger.d(TAG, "📍 Step 4: Failure path")
+                    Logger.d(TAG, "📍 Step 5: Failure path")
                 }
                 Logger.e(TAG, "❌ Sync failed: ${result.errorMessage}")
                 NotificationHelper.showSyncError(
@@ -126,6 +173,32 @@ class SyncWorker(
                 }
                 Result.failure()
             }
+        } catch (e: CancellationException) {
+            // ⭐ Job wurde gecancelt - KEIN FEHLER!
+            // Gründe: App-Update, Doze Mode, Battery Optimization, Network Constraint, etc.
+            if (BuildConfig.DEBUG) {
+                Logger.d(TAG, "═══════════════════════════════════════")
+            }
+            Logger.d(TAG, "⏹️ Job was cancelled (normal - update/doze/constraints)")
+            Logger.d(TAG, "   Reason could be: App update, Doze mode, Battery opt, Network disconnect")
+            Logger.d(TAG, "   This is expected Android behavior - not an error!")
+            
+            try {
+                // UI-Refresh trotzdem triggern (falls MainActivity geöffnet)
+                broadcastSyncCompleted(false, 0)
+            } catch (broadcastError: Exception) {
+                Logger.e(TAG, "Failed to broadcast after cancellation", broadcastError)
+            }
+            
+            if (BuildConfig.DEBUG) {
+                Logger.d(TAG, "✅ SyncWorker.doWork() SUCCESS (cancelled, no error)")
+                Logger.d(TAG, "═══════════════════════════════════════")
+            }
+            
+            // ⚠️ WICHTIG: Result.success() zurückgeben!
+            // Cancellation ist KEIN Fehler, WorkManager soll nicht retries machen
+            Result.success()
+            
         } catch (e: Exception) {
             if (BuildConfig.DEBUG) {
                 Logger.d(TAG, "═══════════════════════════════════════")
@@ -168,4 +241,69 @@ class SyncWorker(
         LocalBroadcastManager.getInstance(applicationContext).sendBroadcast(intent)
         Logger.d(TAG, "📡 Broadcast sent: success=$success, count=$count")
     }
+    
+    /**
+     * Prüft ob Server längere Zeit unreachable und zeigt ggf. Warnung (v1.1.2)
+     * - Nur wenn Auto-Sync aktiviert
+     * - Nur wenn schon mal erfolgreich gesynct
+     * - Nur wenn >24h seit letztem erfolgreichen Sync
+     * - Throttling: Max. 1 Warnung pro 24h
+     */
+    private fun checkAndShowSyncWarning(syncService: WebDavSyncService) {
+        try {
+            val prefs = applicationContext.getSharedPreferences(
+                dev.dettmer.simplenotes.utils.Constants.PREFS_NAME,
+                android.content.Context.MODE_PRIVATE
+            )
+            
+            // Check 1: Auto-Sync aktiviert?
+            val autoSyncEnabled = prefs.getBoolean(
+                dev.dettmer.simplenotes.utils.Constants.KEY_AUTO_SYNC,
+                false
+            )
+            if (!autoSyncEnabled) {
+                Logger.d(TAG, "⏭️ Auto-Sync disabled - no warning needed")
+                return
+            }
+            
+            // Check 2: Schon mal erfolgreich gesynct?
+            val lastSuccessfulSync = syncService.getLastSuccessfulSyncTimestamp()
+            if (lastSuccessfulSync == 0L) {
+                Logger.d(TAG, "⏭️ Never synced successfully - no warning needed")
+                return
+            }
+            
+            // Check 3: >24h seit letztem erfolgreichen Sync?
+            val now = System.currentTimeMillis()
+            val timeSinceLastSync = now - lastSuccessfulSync
+            if (timeSinceLastSync < dev.dettmer.simplenotes.utils.Constants.SYNC_WARNING_THRESHOLD_MS) {
+                Logger.d(TAG, "⏭️ Last successful sync <24h ago - no warning needed")
+                return
+            }
+            
+            // Check 4: Throttling - schon Warnung in letzten 24h gezeigt?
+            val lastWarningShown = prefs.getLong(
+                dev.dettmer.simplenotes.utils.Constants.KEY_LAST_SYNC_WARNING_SHOWN,
+                0L
+            )
+            if (now - lastWarningShown < dev.dettmer.simplenotes.utils.Constants.SYNC_WARNING_THRESHOLD_MS) {
+                Logger.d(TAG, "⏭️ Warning already shown in last 24h - throttling")
+                return
+            }
+            
+            // Zeige Warnung
+            val hoursSinceLastSync = timeSinceLastSync / (1000 * 60 * 60)
+            NotificationHelper.showSyncWarning(applicationContext, hoursSinceLastSync)
+            
+            // Speichere Zeitpunkt der Warnung
+            prefs.edit()
+                .putLong(dev.dettmer.simplenotes.utils.Constants.KEY_LAST_SYNC_WARNING_SHOWN, now)
+                .apply()
+            
+            Logger.d(TAG, "⚠️ Sync warning shown: Server unreachable for ${hoursSinceLastSync}h")
+            
+        } catch (e: Exception) {
+            Logger.e(TAG, "Failed to check/show sync warning", e)
+        }
+    }
 }

android/app/src/main/java/dev/dettmer/simplenotes/sync/WifiSyncReceiver.kt

@@ -28,6 +28,7 @@ class WifiSyncReceiver : BroadcastReceiver() {
         }
     }
     
+    @Suppress("ReturnCount") // Early returns for WiFi validation checks
     private fun isConnectedToHomeWifi(context: Context): Boolean {
         val prefs = context.getSharedPreferences(Constants.PREFS_NAME, Context.MODE_PRIVATE)
         val homeSSID = prefs.getString(Constants.KEY_HOME_SSID, null) ?: return false

android/app/src/main/java/dev/dettmer/simplenotes/utils/Constants.kt

@@ -10,10 +10,26 @@ object Constants {
     const val KEY_AUTO_SYNC = "auto_sync_enabled"
     const val KEY_LAST_SYNC = "last_sync_timestamp"
     
+    // 🔥 v1.1.2: Last Successful Sync Monitoring
+    const val KEY_LAST_SUCCESSFUL_SYNC = "last_successful_sync_time"
+    const val KEY_LAST_SYNC_WARNING_SHOWN = "last_sync_warning_shown_time"
+    const val SYNC_WARNING_THRESHOLD_MS = 24 * 60 * 60 * 1000L  // 24h
+    
     // 🔥 NEU: Sync Interval Configuration
     const val PREF_SYNC_INTERVAL_MINUTES = "sync_interval_minutes"
     const val DEFAULT_SYNC_INTERVAL_MINUTES = 30L
     
+    // 🔥 v1.2.0: Markdown Export/Import
+    const val KEY_MARKDOWN_EXPORT = "markdown_export_enabled"
+    const val KEY_MARKDOWN_AUTO_IMPORT = "markdown_auto_import_enabled"
+    
+    // 🔥 v1.3.0: Performance & Multi-Device Sync
+    const val KEY_ALWAYS_CHECK_SERVER = "always_check_server"
+    const val KEY_ALWAYS_DELETE_FROM_SERVER = "always_delete_from_server"
+    
+    // 🔥 v1.3.1: Debug & Logging
+    const val KEY_FILE_LOGGING_ENABLED = "file_logging_enabled"
+    
     // WorkManager
     const val SYNC_WORK_TAG = "notes_sync"
     const val SYNC_DELAY_SECONDS = 5L

android/app/src/main/java/dev/dettmer/simplenotes/utils/Extensions.kt

@@ -7,6 +7,9 @@ import java.util.Date
 import java.util.Locale
 import java.util.concurrent.TimeUnit
 
+private const val DAYS_THRESHOLD = 7L
+private const val TRUNCATE_SUFFIX_LENGTH = 3
+
 // Toast Extensions
 fun Context.showToast(message: String, duration: Int = Toast.LENGTH_SHORT) {
     Toast.makeText(this, message, duration).show()
@@ -27,7 +30,7 @@ fun Long.toReadableTime(): String {
             val hours = TimeUnit.MILLISECONDS.toHours(diff)
             "Vor $hours Std"
         }
-        diff < TimeUnit.DAYS.toMillis(7) -> {
+        diff < TimeUnit.DAYS.toMillis(DAYS_THRESHOLD) -> {
             val days = TimeUnit.MILLISECONDS.toDays(diff)
             "Vor $days Tagen"
         }
@@ -41,7 +44,7 @@ fun Long.toReadableTime(): String {
 // Truncate long strings
 fun String.truncate(maxLength: Int): String {
     return if (length > maxLength) {
-        substring(0, maxLength - 3) + "..."
+        substring(0, maxLength - TRUNCATE_SUFFIX_LENGTH) + "..."
     } else {
         this
     }

android/app/src/main/java/dev/dettmer/simplenotes/utils/Logger.kt

@@ -5,7 +5,6 @@ import android.util.Log
 import dev.dettmer.simplenotes.BuildConfig
 import java.io.File
 import java.io.FileWriter
-import java.io.PrintWriter
 import java.text.SimpleDateFormat
 import java.util.*
 
@@ -15,10 +14,34 @@ import java.util.*
  */
 object Logger {
     
+    private const val MAX_LOG_ENTRIES = 500 // Nur letzte 500 Einträge
+    
     private var fileLoggingEnabled = false
     private var logFile: File? = null
+    private var appContext: Context? = null
     private val dateFormat = SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS", Locale.getDefault())
-    private val maxLogEntries = 500 // Nur letzte 500 Einträge
+    
+    /**
+     * Setzt den File-Logging Status (für UI Toggle)
+     */
+    fun setFileLoggingEnabled(enabled: Boolean) {
+        fileLoggingEnabled = enabled
+        if (!enabled) {
+            logFile = null
+        }
+    }
+    
+    /**
+     * Gibt zurück, ob File-Logging aktiviert ist
+     */
+    fun isFileLoggingEnabled(): Boolean = fileLoggingEnabled
+    
+    /**
+     * Initialisiert den Logger mit App-Context
+     */
+    fun init(context: Context) {
+        appContext = context.applicationContext
+    }
     
     /**
      * Aktiviert File-Logging für Debugging
@@ -50,11 +73,47 @@ object Logger {
      */
     fun getLogFile(): File? = logFile
     
+    /**
+     * Gibt Log-Datei mit Context zurück (für SettingsActivity)
+     */
+    fun getLogFile(context: Context): File? {
+        if (logFile == null && fileLoggingEnabled) {
+            logFile = File(context.filesDir, "simplenotes_debug.log")
+        }
+        return logFile
+    }
+    
+    /**
+     * Löscht die Log-Datei
+     */
+    fun clearLogFile(context: Context): Boolean {
+        return try {
+            val file = File(context.filesDir, "simplenotes_debug.log")
+            if (file.exists()) {
+                file.delete()
+                logFile = null
+                true
+            } else {
+                false
+            }
+        } catch (e: Exception) {
+            Log.e("Logger", "Failed to clear log file", e)
+            false
+        }
+    }
+    
     /**
      * Schreibt Log-Eintrag in Datei
      */
     private fun writeToFile(level: String, tag: String, message: String, throwable: Throwable? = null) {
-        if (!fileLoggingEnabled || logFile == null) return
+        if (!fileLoggingEnabled) return
+        
+        // Lazy-init logFile mit appContext
+        if (logFile == null && appContext != null) {
+            logFile = File(appContext!!.filesDir, "simplenotes_debug.log")
+        }
+        
+        if (logFile == null) return
         
         try {
             val timestamp = dateFormat.format(Date())
@@ -80,13 +139,13 @@ object Logger {
     }
     
     /**
-     * Begrenzt Log-Datei auf maxLogEntries
+     * Begrenzt Log-Datei auf MAX_LOG_ENTRIES
      */
     private fun trimLogFile() {
         try {
             val lines = logFile?.readLines() ?: return
-            if (lines.size > maxLogEntries) {
+            if (lines.size > MAX_LOG_ENTRIES) {
-                val trimmed = lines.takeLast(maxLogEntries)
+                val trimmed = lines.takeLast(MAX_LOG_ENTRIES)
                 logFile?.writeText(trimmed.joinToString("\n") + "\n")
             }
         } catch (e: Exception) {

android/app/src/main/java/dev/dettmer/simplenotes/utils/NotificationHelper.kt

@@ -6,17 +6,21 @@ import android.app.PendingIntent
 import android.content.Context
 import android.content.Intent
 import android.os.Build
+import android.os.Handler
+import android.os.Looper
 import androidx.core.app.NotificationCompat
 import androidx.core.app.NotificationManagerCompat
 import dev.dettmer.simplenotes.MainActivity
 
 object NotificationHelper {
     
+    private const val TAG = "NotificationHelper"
     private const val CHANNEL_ID = "notes_sync_channel"
     private const val CHANNEL_NAME = "Notizen Synchronisierung"
     private const val CHANNEL_DESCRIPTION = "Benachrichtigungen über Sync-Status"
     private const val NOTIFICATION_ID = 1001
     private const val SYNC_NOTIFICATION_ID = 2
+    private const val AUTO_CANCEL_TIMEOUT_MS = 30_000L
     
     /**
      * Erstellt Notification Channel (Android 8.0+)
@@ -38,6 +42,17 @@ object NotificationHelper {
         }
     }
     
+    /**
+     * Löscht alle Sync-Notifications
+     * Sollte beim App-Start aufgerufen werden um alte Notifications zu entfernen
+     */
+    fun clearSyncNotifications(context: Context) {
+        val manager = context.getSystemService(Context.NOTIFICATION_SERVICE) 
+            as NotificationManager
+        manager.cancel(SYNC_NOTIFICATION_ID)
+        Logger.d(TAG, "🗑️ Cleared old sync notifications")
+    }
+    
     /**
      * Zeigt Erfolgs-Notification nach Sync
      */
@@ -240,6 +255,7 @@ object NotificationHelper {
     
     /**
      * Zeigt Fehler-Notification
+     * Auto-Cancel nach 30 Sekunden
      */
     fun showSyncError(context: Context, message: String) {
         // PendingIntent für App-Öffnung
@@ -266,5 +282,47 @@ object NotificationHelper {
         val manager = context.getSystemService(Context.NOTIFICATION_SERVICE) 
             as NotificationManager
         manager.notify(SYNC_NOTIFICATION_ID, notification)
+        
+        // ⭐ NEU: Auto-Cancel nach 30 Sekunden
+        Handler(Looper.getMainLooper()).postDelayed({
+            manager.cancel(SYNC_NOTIFICATION_ID)
+            Logger.d(TAG, "🗑️ Auto-cancelled error notification after 30s timeout")
+        }, AUTO_CANCEL_TIMEOUT_MS)
+    }
+    
+    /**
+     * Zeigt Warnung wenn Server längere Zeit nicht erreichbar (v1.1.2)
+     * Throttling: Max. 1 Warnung pro 24h
+     */
+    fun showSyncWarning(context: Context, hoursSinceLastSync: Long) {
+        // PendingIntent für App-Öffnung
+        val intent = Intent(context, MainActivity::class.java).apply {
+            flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TOP
+        }
+        val pendingIntent = PendingIntent.getActivity(
+            context,
+            0,
+            intent,
+            PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT
+        )
+        
+        val notification = NotificationCompat.Builder(context, CHANNEL_ID)
+            .setSmallIcon(android.R.drawable.stat_notify_error)
+            .setContentTitle("⚠️ Sync-Warnung")
+            .setContentText("Server seit ${hoursSinceLastSync}h nicht erreichbar")
+            .setStyle(NotificationCompat.BigTextStyle()
+                .bigText("Der WebDAV-Server ist seit ${hoursSinceLastSync} Stunden nicht erreichbar. " +
+                        "Bitte prüfe deine Netzwerkverbindung oder Server-Einstellungen."))
+            .setPriority(NotificationCompat.PRIORITY_DEFAULT)
+            .setCategory(NotificationCompat.CATEGORY_STATUS)
+            .setContentIntent(pendingIntent)
+            .setAutoCancel(true)
+            .build()
+        
+        val manager = context.getSystemService(Context.NOTIFICATION_SERVICE) 
+            as NotificationManager
+        manager.notify(SYNC_NOTIFICATION_ID, notification)
+        
+        Logger.d(TAG, "⚠️ Showed sync warning: Server unreachable for ${hoursSinceLastSync}h")
     }
 }

android/app/src/main/java/dev/dettmer/simplenotes/utils/SyncException.kt

@@ -0,0 +1,21 @@
+package dev.dettmer.simplenotes.utils
+
+/**
+ * Exception für Sync-spezifische Fehler
+ * 
+ * Verwendet anstelle von generischen Exceptions für bessere
+ * Fehlerbehandlung und klarere Fehlermeldungen.
+ */
+class SyncException(
+    message: String,
+    cause: Throwable? = null
+) : Exception(message, cause)
+
+/**
+ * Exception für Validierungsfehler
+ * 
+ * Verwendet für ungültige Eingaben oder Konfigurationsfehler.
+ */
+class ValidationException(
+    message: String
+) : IllegalArgumentException(message)

android/app/src/main/java/dev/dettmer/simplenotes/utils/UrlValidator.kt

@@ -0,0 +1,122 @@
+package dev.dettmer.simplenotes.utils
+
+import java.net.URL
+
+/**
+ * URL Validator für Network Security (v1.1.2)
+ * Erlaubt HTTP nur für lokale Netzwerke (RFC 1918 Private IPs)
+ */
+object UrlValidator {
+    
+    // RFC 1918 Private IP Ranges
+    private const val PRIVATE_CLASS_A_FIRST_OCTET = 10
+    private const val PRIVATE_CLASS_B_FIRST_OCTET = 172
+    private const val PRIVATE_CLASS_B_SECOND_OCTET_MIN = 16
+    private const val PRIVATE_CLASS_B_SECOND_OCTET_MAX = 31
+    private const val PRIVATE_CLASS_C_FIRST_OCTET = 192
+    private const val PRIVATE_CLASS_C_SECOND_OCTET = 168
+    private const val LOCALHOST_FIRST_OCTET = 127
+    private const val OCTET_MAX_VALUE = 255
+    
+    /**
+     * Prüft ob eine URL eine lokale/private Adresse ist
+     * Erlaubt:
+     * - 192.168.x.x (Class C private)
+     * - 10.x.x.x (Class A private)
+     * - 172.16.x.x - 172.31.x.x (Class B private)
+     * - 127.x.x.x (Localhost)
+     * - .local domains (mDNS/Bonjour)
+     */
+    @Suppress("ReturnCount") // Early returns for validation checks are clearer
+    fun isLocalUrl(url: String): Boolean {
+        return try {
+            val parsedUrl = URL(url)
+            val host = parsedUrl.host.lowercase()
+            
+            // Check for .local domains (e.g., nas.local)
+            if (host.endsWith(".local")) {
+                return true
+            }
+            
+            // Check for localhost
+            if (host == "localhost" || host == "127.0.0.1") {
+                return true
+            }
+            
+            // Parse IP address if it's numeric
+            val ipPattern = """^(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$""".toRegex()
+            val match = ipPattern.find(host)
+            
+            if (match != null) {
+                val octets = match.groupValues.drop(1).map { it.toInt() }
+                
+                // Validate octets are in range 0-255
+                if (octets.any { it > OCTET_MAX_VALUE }) {
+                    return false
+                }
+                
+                // Extract octets individually (destructuring with 4 elements triggers detekt warning)
+                val o1 = octets[0]
+                val o2 = octets[1]
+                
+                // Check RFC 1918 private IP ranges
+                return when {
+                    // 10.0.0.0/8 (10.0.0.0 - 10.255.255.255)
+                    o1 == PRIVATE_CLASS_A_FIRST_OCTET -> true
+                    
+                    // 172.16.0.0/12 (172.16.0.0 - 172.31.255.255)
+                    o1 == PRIVATE_CLASS_B_FIRST_OCTET &&
+                        o2 in PRIVATE_CLASS_B_SECOND_OCTET_MIN..PRIVATE_CLASS_B_SECOND_OCTET_MAX -> true
+                    
+                    // 192.168.0.0/16 (192.168.0.0 - 192.168.255.255)
+                    o1 == PRIVATE_CLASS_C_FIRST_OCTET &&
+                        o2 == PRIVATE_CLASS_C_SECOND_OCTET -> true
+                    
+                    // 127.0.0.0/8 (Localhost)
+                    o1 == LOCALHOST_FIRST_OCTET -> true
+                    
+                    else -> false
+                }
+            }
+            
+            // Not a recognized local address
+            false
+        } catch (e: Exception) {
+            Logger.w("UrlValidator", "Failed to parse URL: ${e.message}")
+            false
+        }
+    }
+    
+    /**
+     * Validiert ob HTTP URL erlaubt ist
+     * @return Pair<Boolean, String?> - (isValid, errorMessage)
+     */
+    fun validateHttpUrl(url: String): Pair<Boolean, String?> {
+        return try {
+            val parsedUrl = URL(url)
+            
+            // HTTPS ist immer erlaubt
+            if (parsedUrl.protocol.equals("https", ignoreCase = true)) {
+                return Pair(true, null)
+            }
+            
+            // HTTP nur für lokale URLs erlaubt
+            if (parsedUrl.protocol.equals("http", ignoreCase = true)) {
+                if (isLocalUrl(url)) {
+                    return Pair(true, null)
+                } else {
+                    return Pair(
+                        false,
+                        "HTTP ist nur für lokale Server erlaubt (z.B. 192.168.x.x, 10.x.x.x, nas.local). " +
+                        "Für öffentliche Server verwende bitte HTTPS."
+                    )
+                }
+            }
+            
+            // Anderes Protokoll
+            Pair(false, "Ungültiges Protokoll: ${parsedUrl.protocol}. Bitte verwende HTTP oder HTTPS.")
+        } catch (e: Exception) {
+            Pair(false, "Ungültige URL: ${e.message}")
+        }
+    }
+}

android/app/src/main/res/drawable/ic_launcher_background.xml

@@ -1,170 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<vector xmlns:android="http://schemas.android.com/apk/res/android"
-    android:width="108dp"
-    android:height="108dp"
-    android:viewportWidth="108"
-    android:viewportHeight="108">
-    <path
-        android:fillColor="#3DDC84"
-        android:pathData="M0,0h108v108h-108z" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M9,0L9,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M19,0L19,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M29,0L29,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M39,0L39,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M49,0L49,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M59,0L59,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M69,0L69,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M79,0L79,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M89,0L89,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M99,0L99,108"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,9L108,9"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,19L108,19"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,29L108,29"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,39L108,39"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,49L108,49"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,59L108,59"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,69L108,69"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,79L108,79"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,89L108,89"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M0,99L108,99"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M19,29L89,29"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M19,39L89,39"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M19,49L89,49"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M19,59L89,59"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M19,69L89,69"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M19,79L89,79"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M29,19L29,89"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M39,19L39,89"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M49,19L49,89"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M59,19L59,89"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M69,19L69,89"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-    <path
-        android:fillColor="#00000000"
-        android:pathData="M79,19L79,89"
-        android:strokeWidth="0.8"
-        android:strokeColor="#33FFFFFF" />
-</vector>

android/app/src/main/res/drawable/ic_launcher_foreground.xml

@@ -1,30 +0,0 @@
-<vector xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:aapt="http://schemas.android.com/aapt"
-    android:width="108dp"
-    android:height="108dp"
-    android:viewportWidth="108"
-    android:viewportHeight="108">
-    <path android:pathData="M31,63.928c0,0 6.4,-11 12.1,-13.1c7.2,-2.6 26,-1.4 26,-1.4l38.1,38.1L107,108.928l-32,-1L31,63.928z">
-        <aapt:attr name="android:fillColor">
-            <gradient
-                android:endX="85.84757"
-                android:endY="92.4963"
-                android:startX="42.9492"
-                android:startY="49.59793"
-                android:type="linear">
-                <item
-                    android:color="#44000000"
-                    android:offset="0.0" />
-                <item
-                    android:color="#00000000"
-                    android:offset="1.0" />
-            </gradient>
-        </aapt:attr>
-    </path>
-    <path
-        android:fillColor="#FFFFFF"
-        android:fillType="nonZero"
-        android:pathData="M65.3,45.828l3.8,-6.6c0.2,-0.4 0.1,-0.9 -0.3,-1.1c-0.4,-0.2 -0.9,-0.1 -1.1,0.3l-3.9,6.7c-6.3,-2.8 -13.4,-2.8 -19.7,0l-3.9,-6.7c-0.2,-0.4 -0.7,-0.5 -1.1,-0.3C38.8,38.328 38.7,38.828 38.9,39.228l3.8,6.6C36.2,49.428 31.7,56.028 31,63.928h46C76.3,56.028 71.8,49.428 65.3,45.828zM43.4,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2c-0.3,-0.7 -0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C45.3,56.528 44.5,57.328 43.4,57.328L43.4,57.328zM64.6,57.328c-0.8,0 -1.5,-0.5 -1.8,-1.2s-0.1,-1.5 0.4,-2.1c0.5,-0.5 1.4,-0.7 2.1,-0.4c0.7,0.3 1.2,1 1.2,1.8C66.5,56.528 65.6,57.328 64.6,57.328L64.6,57.328z"
-        android:strokeWidth="1"
-        android:strokeColor="#00000000" />
-</vector>

android/app/src/main/res/layout/activity_editor.xml

@@ -14,7 +14,7 @@
         android:layout_width="match_parent"
         android:layout_height="?attr/actionBarSize"
         android:elevation="0dp"
-        app:navigationIcon="@android:drawable/ic_menu_close_clear_cancel"
+        app:navigationIcon="?attr/homeAsUpIndicator"
         app:title="@string/edit_note"
         app:titleTextAppearance="@style/TextAppearance.Material3.TitleLarge" />
 

android/app/src/main/res/layout/activity_main.xml

@@ -22,16 +22,57 @@
             app:title="@string/app_name"
             app:titleTextAppearance="@style/TextAppearance.Material3.TitleLarge" />
 
+        <!-- 🔄 v1.3.1: Sync Status Banner -->
+        <LinearLayout
+            android:id="@+id/syncStatusBanner"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="horizontal"
+            android:gravity="center_vertical"
+            android:paddingHorizontal="16dp"
+            android:paddingVertical="8dp"
+            android:background="?attr/colorPrimaryContainer"
+            android:visibility="gone">
+
+            <com.google.android.material.progressindicator.CircularProgressIndicator
+                android:id="@+id/syncProgressIndicator"
+                android:layout_width="24dp"
+                android:layout_height="24dp"
+                android:indeterminate="true"
+                app:indicatorSize="24dp"
+                app:trackThickness="3dp"
+                app:indicatorColor="?attr/colorOnPrimaryContainer" />
+
+            <TextView
+                android:id="@+id/syncStatusText"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_weight="1"
+                android:layout_marginStart="12dp"
+                android:text="@string/sync_status_syncing"
+                android:textAppearance="@style/TextAppearance.Material3.BodyMedium"
+                android:textColor="?attr/colorOnPrimaryContainer" />
+
+        </LinearLayout>
+
     </com.google.android.material.appbar.AppBarLayout>
 
-    <!-- RecyclerView mit größerem Padding für Material 3 -->
+    <!-- SwipeRefreshLayout für Pull-to-Refresh (v1.1.2) -->
-    <androidx.recyclerview.widget.RecyclerView
+    <androidx.swiperefreshlayout.widget.SwipeRefreshLayout
-        android:id="@+id/recyclerViewNotes"
+        android:id="@+id/swipeRefreshLayout"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:clipToPadding="false"
+        app:layout_behavior="@string/appbar_scrolling_view_behavior">
-        android:padding="16dp"
+
-        app:layout_behavior="@string/appbar_scrolling_view_behavior" />
+        <!-- RecyclerView mit größerem Padding für Material 3 -->
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/recyclerViewNotes"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:clipToPadding="false"
+            android:padding="16dp" />
+
+    </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>
 
     <!-- Material 3 Empty State Card -->
     <com.google.android.material.card.MaterialCardView

android/app/src/main/res/layout/activity_settings.xml

@@ -30,17 +30,6 @@
             android:orientation="vertical"
             android:padding="16dp">
 
-            <!-- Auto-Save Status Indicator -->
-            <com.google.android.material.chip.Chip
-                android:id="@+id/chipAutoSaveStatus"
-                android:layout_width="wrap_content"
-                android:layout_height="wrap_content"
-                android:layout_gravity="center_horizontal"
-                android:layout_marginBottom="12dp"
-                android:visibility="gone"
-                android:textSize="12sp"
-                app:chipIconEnabled="false" />
-
             <!-- Material 3 Card: Server Configuration -->
             <com.google.android.material.card.MaterialCardView
                 android:layout_width="match_parent"
@@ -63,15 +52,65 @@
                         android:textAppearance="@style/TextAppearance.Material3.TitleMedium"
                         android:layout_marginBottom="16dp" />
 
-                    <!-- Server URL with Icon -->
+                    <!-- Protocol Selection -->
-                    <com.google.android.material.textfield.TextInputLayout
+                    <TextView
                         android:layout_width="match_parent"
                         android:layout_height="wrap_content"
-                        android:hint="@string/server_url"
+                        android:text="Verbindungstyp"
+                        android:textAppearance="@style/TextAppearance.Material3.LabelLarge"
+                        android:layout_marginBottom="8dp" />
+
+                    <RadioGroup
+                        android:id="@+id/protocolRadioGroup"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:orientation="horizontal"
+                        android:layout_marginBottom="16dp">
+
+                        <com.google.android.material.radiobutton.MaterialRadioButton
+                            android:id="@+id/radioHttp"
+                            android:layout_width="0dp"
+                            android:layout_height="wrap_content"
+                            android:layout_weight="1"
+                            android:text="🏠 Intern (HTTP)"
+                            android:textAppearance="@style/TextAppearance.Material3.BodyMedium"
+                            android:checked="false" />
+
+                        <com.google.android.material.radiobutton.MaterialRadioButton
+                            android:id="@+id/radioHttps"
+                            android:layout_width="0dp"
+                            android:layout_height="wrap_content"
+                            android:layout_weight="1"
+                            android:text="🌐 Extern (HTTPS)"
+                            android:textAppearance="@style/TextAppearance.Material3.BodyMedium"
+                            android:checked="true" />
+
+                    </RadioGroup>
+
+                    <!-- Helper Text for Protocol Selection -->
+                    <TextView
+                        android:id="@+id/protocolHintText"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="HTTP nur für lokale Netzwerke (z.B. 192.168.x.x, 10.x.x.x)"
+                        android:textAppearance="@style/TextAppearance.Material3.BodySmall"
+                        android:textColor="?attr/colorOnSurfaceVariant"
+                        android:layout_marginBottom="16dp"
+                        android:paddingStart="4dp"
+                        android:paddingEnd="4dp" />
+
+                    <!-- Server URL with Icon -->
+                    <com.google.android.material.textfield.TextInputLayout
+                        android:id="@+id/textInputLayoutServerUrl"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:hint="Server-Adresse"
                         android:layout_marginBottom="12dp"
                         style="@style/Widget.Material3.TextInputLayout.OutlinedBox"
                         app:startIconDrawable="@android:drawable/ic_menu_compass"
                         app:endIconMode="clear_text"
+                        app:helperText="z.B. http://192.168.0.188:8080/notes"
+                        app:helperTextEnabled="true"
                         app:boxCornerRadiusTopStart="12dp"
                         app:boxCornerRadiusTopEnd="12dp"
                         app:boxCornerRadiusBottomStart="12dp"
@@ -185,7 +224,7 @@
 
             </com.google.android.material.card.MaterialCardView>
 
-            <!-- Material 3 Card: Auto-Sync Settings -->
+            <!-- Material 3 Card: Synchronisation Settings (Auto-Sync + Interval) -->
             <com.google.android.material.card.MaterialCardView
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
@@ -230,6 +269,7 @@
                     <LinearLayout
                         android:layout_width="match_parent"
                         android:layout_height="wrap_content"
+                        android:layout_marginBottom="16dp"
                         android:orientation="horizontal"
                         android:gravity="center_vertical">
 
@@ -247,87 +287,22 @@
 
                     </LinearLayout>
 
-                </LinearLayout>
+                    <!-- Divider -->
-
+                    <View
-            </com.google.android.material.card.MaterialCardView>
-
-            <!-- Material 3 Card: Backup & Restore -->
-            <com.google.android.material.card.MaterialCardView
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:layout_marginBottom="16dp"
-                style="@style/Widget.Material3.CardView.Elevated"
-                app:cardCornerRadius="16dp">
-
-                <LinearLayout
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:orientation="vertical"
-                    android:padding="20dp">
-
-                    <!-- Section Header -->
-                    <TextView
                         android:layout_width="match_parent"
-                        android:layout_height="wrap_content"
+                        android:layout_height="1dp"
-                        android:text="@string/backup_restore_title"
+                        android:layout_marginVertical="16dp"
-                        android:textAppearance="@style/TextAppearance.Material3.TitleMedium"
+                        android:background="?attr/colorOutlineVariant" />
-                        android:layout_marginBottom="12dp" />
 
-                    <!-- Warning Info Card -->
+                    <!-- Sync Interval Section -->
-                    <com.google.android.material.card.MaterialCardView
-                        android:layout_width="match_parent"
-                        android:layout_height="wrap_content"
-                        android:layout_marginBottom="16dp"
-                        app:cardBackgroundColor="?attr/colorErrorContainer"
-                        app:cardCornerRadius="12dp"
-                        app:cardElevation="0dp">
-
-                        <TextView
-                            android:layout_width="match_parent"
-                            android:layout_height="wrap_content"
-                            android:padding="16dp"
-                            android:text="@string/backup_restore_warning"
-                            android:textAppearance="@style/TextAppearance.Material3.BodySmall"
-                            android:textColor="?attr/colorOnErrorContainer"
-                            android:lineSpacingMultiplier="1.3" />
-
-                    </com.google.android.material.card.MaterialCardView>
-
-                    <!-- Restore Button -->
-                    <Button
-                        android:id="@+id/buttonRestoreFromServer"
-                        android:layout_width="match_parent"
-                        android:layout_height="wrap_content"
-                        android:text="@string/restore_from_server"
-                        style="@style/Widget.Material3.Button.TonalButton" />
-
-                </LinearLayout>
-
-            </com.google.android.material.card.MaterialCardView>
-
-            <!-- Material 3 Card: Sync Interval Configuration -->
-            <com.google.android.material.card.MaterialCardView
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:layout_marginBottom="16dp"
-                style="@style/Widget.Material3.CardView.Elevated"
-                app:cardCornerRadius="16dp">
-
-                <LinearLayout
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:orientation="vertical"
-                    android:padding="20dp">
-
-                    <!-- Section Header -->
                     <TextView
                         android:layout_width="match_parent"
                         android:layout_height="wrap_content"
                         android:text="Sync-Intervall"
-                        android:textAppearance="@style/TextAppearance.Material3.TitleMedium"
+                        android:textAppearance="@style/TextAppearance.Material3.LabelLarge"
                         android:layout_marginBottom="12dp" />
 
-                    <!-- Info Card -->
+                    <!-- Interval Info Card -->
                     <com.google.android.material.card.MaterialCardView
                         android:layout_width="match_parent"
                         android:layout_height="wrap_content"
@@ -412,6 +387,201 @@
 
             </com.google.android.material.card.MaterialCardView>
 
+            <!-- Material 3 Card: Markdown Desktop-Integration (v1.2.0) -->
+            <com.google.android.material.card.MaterialCardView
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginBottom="16dp"
+                style="@style/Widget.Material3.CardView.Elevated"
+                app:cardCornerRadius="16dp">
+
+                <LinearLayout
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:orientation="vertical"
+                    android:padding="20dp">
+
+                    <!-- Section Header -->
+                    <TextView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="Markdown Desktop-Integration"
+                        android:textAppearance="@style/TextAppearance.Material3.TitleMedium"
+                        android:layout_marginBottom="12dp" />
+
+                    <!-- Info Card -->
+                    <com.google.android.material.card.MaterialCardView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:layout_marginBottom="16dp"
+                        app:cardBackgroundColor="?attr/colorPrimaryContainer"
+                        app:cardCornerRadius="12dp"
+                        app:cardElevation="0dp">
+
+                        <TextView
+                            android:layout_width="match_parent"
+                            android:layout_height="wrap_content"
+                            android:padding="16dp"
+                            android:text="ℹ️ Exportiert Notizen zusätzlich als .md Dateien. Mounte WebDAV als Netzlaufwerk um mit VS Code, Typora oder jedem Markdown-Editor zu bearbeiten. JSON-Sync bleibt primäres Format."
+                            android:textAppearance="@style/TextAppearance.Material3.BodySmall"
+                            android:textColor="?attr/colorOnPrimaryContainer"
+                            android:lineSpacingMultiplier="1.3" />
+
+                    </com.google.android.material.card.MaterialCardView>
+
+                    <!-- Markdown Auto-Sync Toggle (fusioniert Export + Auto-Import) -->
+                    <LinearLayout
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:layout_marginBottom="8dp"
+                        android:orientation="horizontal"
+                        android:gravity="center_vertical">
+
+                        <TextView
+                            android:layout_width="0dp"
+                            android:layout_height="wrap_content"
+                            android:layout_weight="1"
+                            android:text="🔄 Markdown Auto-Sync"
+                            android:textAppearance="@style/TextAppearance.Material3.BodyLarge" />
+
+                        <androidx.appcompat.widget.SwitchCompat
+                            android:id="@+id/switchMarkdownAutoSync"
+                            android:layout_width="wrap_content"
+                            android:layout_height="wrap_content"
+                            android:checked="false" />
+
+                    </LinearLayout>
+
+                    <!-- Auto-Sync Info Text -->
+                    <TextView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:layout_marginBottom="16dp"
+                        android:text="Synchronisiert Notizen automatisch als .md Dateien (Upload + Download bei jedem Sync)"
+                        android:textAppearance="@style/TextAppearance.Material3.BodySmall"
+                        android:textColor="?attr/colorOnSurfaceVariant" />
+
+                    <!-- Manual Sync Info (nur sichtbar wenn Auto-Sync OFF) -->
+                    <TextView
+                        android:id="@+id/textViewManualSyncInfo"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:layout_marginTop="8dp"
+                        android:layout_marginBottom="8dp"
+                        android:text="Oder synchronisiere Markdown-Dateien manuell:"
+                        android:textAppearance="@style/TextAppearance.Material3.BodyMedium"
+                        android:textColor="?attr/colorOnSurface"
+                        android:visibility="gone" />
+
+                    <!-- Manual Sync Button (nur sichtbar wenn Auto-Sync OFF) -->
+                    <Button
+                        android:id="@+id/buttonManualMarkdownSync"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="Markdown synchronisieren"
+                        android:visibility="gone"
+                        style="@style/Widget.Material3.Button.TonalButton" />
+
+                </LinearLayout>
+
+            </com.google.android.material.card.MaterialCardView>
+
+            <!-- Material 3 Card: Backup & Restore -->
+            <com.google.android.material.card.MaterialCardView
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginBottom="16dp"
+                style="@style/Widget.Material3.CardView.Elevated"
+                app:cardCornerRadius="16dp">
+
+                <LinearLayout
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:orientation="vertical"
+                    android:padding="20dp">
+
+                    <!-- Section Header -->
+                    <TextView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="@string/backup_restore_title"
+                        android:textAppearance="@style/TextAppearance.Material3.TitleMedium"
+                        android:layout_marginBottom="12dp" />
+
+                    <!-- Info Card (anstatt Warning) -->
+                    <com.google.android.material.card.MaterialCardView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:layout_marginBottom="16dp"
+                        app:cardBackgroundColor="?attr/colorPrimaryContainer"
+                        app:cardCornerRadius="12dp"
+                        app:cardElevation="0dp">
+
+                        <TextView
+                            android:layout_width="match_parent"
+                            android:layout_height="wrap_content"
+                            android:padding="16dp"
+                            android:text="ℹ️ Bei jeder Wiederherstellung wird automatisch ein Sicherheits-Backup erstellt."
+                            android:textAppearance="@style/TextAppearance.Material3.BodySmall"
+                            android:textColor="?attr/colorOnPrimaryContainer"
+                            android:lineSpacingMultiplier="1.3" />
+
+                    </com.google.android.material.card.MaterialCardView>
+
+                    <!-- Lokales Backup Sektion -->
+                    <TextView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="Lokales Backup"
+                        android:textAppearance="@style/TextAppearance.Material3.LabelLarge"
+                        android:layout_marginBottom="12dp" />
+
+                    <!-- Backup erstellen Button -->
+                    <Button
+                        android:id="@+id/buttonCreateBackup"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="📥 Backup erstellen"
+                        android:layout_marginBottom="8dp"
+                        style="@style/Widget.Material3.Button.TonalButton" />
+
+                    <!-- Aus Datei wiederherstellen Button -->
+                    <Button
+                        android:id="@+id/buttonRestoreFromFile"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="📤 Aus Datei wiederherstellen"
+                        android:layout_marginBottom="16dp"
+                        style="@style/Widget.Material3.Button.TonalButton" />
+
+                    <!-- Divider -->
+                    <View
+                        android:layout_width="match_parent"
+                        android:layout_height="1dp"
+                        android:background="?attr/colorOutline"
+                        android:layout_marginTop="8dp"
+                        android:layout_marginBottom="16dp" />
+
+                    <!-- Server-Backup Sektion -->
+                    <TextView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="Server-Backup"
+                        android:textAppearance="@style/TextAppearance.Material3.LabelLarge"
+                        android:layout_marginBottom="12dp" />
+
+                    <!-- Vom Server wiederherstellen Button -->
+                    <Button
+                        android:id="@+id/buttonRestoreFromServer"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="🔄 Vom Server wiederherstellen"
+                        style="@style/Widget.Material3.Button.TonalButton" />
+
+                </LinearLayout>
+
+            </com.google.android.material.card.MaterialCardView>
+
             <!-- Material 3 Card: About Section -->
             <com.google.android.material.card.MaterialCardView
                 android:layout_width="match_parent"
@@ -579,6 +749,107 @@
 
             </com.google.android.material.card.MaterialCardView>
 
+            <!-- Material 3 Card: Debug Section -->
+            <com.google.android.material.card.MaterialCardView
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginBottom="16dp"
+                style="@style/Widget.Material3.CardView.Elevated"
+                app:cardCornerRadius="16dp">
+
+                <LinearLayout
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:orientation="vertical"
+                    android:padding="20dp">
+
+                    <!-- Section Header -->
+                    <TextView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="Debug &amp; Diagnose"
+                        android:textAppearance="@style/TextAppearance.Material3.TitleMedium"
+                        android:layout_marginBottom="16dp" />
+
+                    <!-- File Logging Toggle -->
+                    <com.google.android.material.card.MaterialCardView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:layout_marginBottom="12dp"
+                        app:cardBackgroundColor="?attr/colorSurfaceVariant"
+                        app:cardCornerRadius="12dp"
+                        app:cardElevation="0dp">
+
+                        <LinearLayout
+                            android:layout_width="match_parent"
+                            android:layout_height="wrap_content"
+                            android:orientation="horizontal"
+                            android:padding="16dp"
+                            android:gravity="center_vertical">
+
+                            <LinearLayout
+                                android:layout_width="0dp"
+                                android:layout_height="wrap_content"
+                                android:layout_weight="1"
+                                android:orientation="vertical">
+
+                                <TextView
+                                    android:layout_width="match_parent"
+                                    android:layout_height="wrap_content"
+                                    android:text="📝 Datei-Logging"
+                                    android:textAppearance="@style/TextAppearance.Material3.LabelLarge"
+                                    android:textColor="?attr/colorPrimary"
+                                    android:layout_marginBottom="4dp" />
+
+                                <TextView
+                                    android:layout_width="match_parent"
+                                    android:layout_height="wrap_content"
+                                    android:text="Sync-Logs in Datei speichern"
+                                    android:textAppearance="@style/TextAppearance.Material3.BodyMedium" />
+
+                            </LinearLayout>
+
+                            <com.google.android.material.materialswitch.MaterialSwitch
+                                android:id="@+id/switchFileLogging"
+                                android:layout_width="wrap_content"
+                                android:layout_height="wrap_content" />
+
+                        </LinearLayout>
+
+                    </com.google.android.material.card.MaterialCardView>
+
+                    <!-- F-Droid Privacy Notice -->
+                    <TextView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="@string/file_logging_privacy_notice"
+                        android:textAppearance="@style/TextAppearance.Material3.BodySmall"
+                        android:textColor="?attr/colorOnSurfaceVariant"
+                        android:layout_marginBottom="16dp"
+                        android:paddingStart="4dp"
+                        android:paddingEnd="4dp" />
+
+                    <!-- Export Logs Button -->
+                    <Button
+                        android:id="@+id/buttonExportLogs"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="📤 Logs exportieren &amp; teilen"
+                        style="@style/Widget.Material3.Button.TonalButton"
+                        android:layout_marginBottom="8dp" />
+
+                    <!-- Clear Logs Button -->
+                    <Button
+                        android:id="@+id/buttonClearLogs"
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="🗑️ Logs löschen"
+                        style="@style/Widget.Material3.Button.OutlinedButton" />
+
+                </LinearLayout>
+
+            </com.google.android.material.card.MaterialCardView>
+
         </LinearLayout>
 
     </ScrollView>

android/app/src/main/res/layout/dialog_delete_confirmation.xml

@@ -15,7 +15,7 @@
         android:layout_gravity="center_horizontal"
         android:layout_marginBottom="16dp"
         android:src="@android:drawable/ic_menu_delete"
-        android:tint="?attr/colorError"
+        app:tint="?attr/colorError"
         android:contentDescription="@string/delete" />
 
     <!-- Title -->

android/app/src/main/res/layout/dialog_server_deletion.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:padding="16dp">
+
+    <CheckBox
+        android:id="@+id/checkboxAlwaysDeleteFromServer"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="Diese Entscheidung merken"
+        android:textAppearance="@style/TextAppearance.Material3.BodyMedium" />
+
+</LinearLayout>

android/app/src/main/res/layout/item_note.xml

@@ -64,7 +64,7 @@
                 android:layout_height="18dp"
                 android:layout_gravity="center_vertical"
                 android:src="@android:drawable/ic_popup_sync"
-                android:tint="?attr/colorPrimary"
+                app:tint="?attr/colorPrimary"
                 android:contentDescription="@string/sync_status" />
 
         </LinearLayout>

android/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -1,6 +1,5 @@
-<?xml version="1.0" encoding="utf-8"?>
 <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
-    <background android:drawable="@drawable/ic_launcher_background" />
+  <background android:drawable="@color/ic_launcher_background"/>
-    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+  <foreground android:drawable="@mipmap/ic_launcher_foreground"/>
-    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+  <monochrome android:drawable="@mipmap/ic_launcher_monochrome"/>
 </adaptive-icon>

android/app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

@@ -1,6 +1,5 @@
-<?xml version="1.0" encoding="utf-8"?>
 <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
-    <background android:drawable="@drawable/ic_launcher_background" />
+  <background android:drawable="@color/ic_launcher_background"/>
-    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+  <foreground android:drawable="@mipmap/ic_launcher_foreground"/>
-    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
+  <monochrome android:drawable="@mipmap/ic_launcher_monochrome"/>
 </adaptive-icon>

android/app/src/main/res/values/colors.xml

@@ -4,6 +4,9 @@
     <color name="black">#FF000000</color>
     <color name="white">#FFFFFFFF</color>
     
+    <!-- Adaptive Icon Background -->
+    <color name="ic_launcher_background">#f9e9c8</color>
+    
     <!-- Material 3 Light Theme Colors -->
     <color name="md_theme_light_primary">#6750A4</color>
     <color name="md_theme_light_onPrimary">#FFFFFF</color>

android/app/src/main/res/values/strings.xml

@@ -57,4 +57,13 @@
     <string name="restore_progress">Stelle Notizen wieder her…</string>
     <string name="restore_success">✓ %d Notizen wiederhergestellt</string>
     <string name="restore_error">Fehler: %s</string>
+    
+    <!-- Sync Status Banner (v1.3.1) -->
+    <string name="sync_status_syncing">Synchronisiere…</string>
+    <string name="sync_status_completed">Synchronisierung abgeschlossen</string>
+    <string name="sync_status_error">Synchronisierung fehlgeschlagen</string>
+    <string name="sync_already_running">Synchronisierung läuft bereits</string>
+    
+    <!-- Debug/Logging Section (v1.3.2) -->
+    <string name="file_logging_privacy_notice">ℹ️ Datenschutz: Logs werden nur lokal auf deinem Gerät gespeichert und niemals an externe Server gesendet. Die Logs enthalten Sync-Aktivitäten zur Fehlerdiagnose. Du kannst sie jederzeit löschen oder exportieren.</string>
 </resources>

android/app/src/main/res/xml/network_security_config.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<network-security-config>
+    <!-- Allow HTTP for all connections during development/testing -->
+    <!-- Production validation happens in UrlValidator.kt to restrict HTTP to:
+         - Private IP ranges: 192.168.x.x, 10.x.x.x, 172.16-31.x.x, 127.x.x.x
+         - .local domains (mDNS/Bonjour)
+         
+         This permissive config is necessary because Android's Network Security Config
+         doesn't support IP-based rules, only domain patterns.
+         We handle security through application-level validation instead. -->
+    <base-config cleartextTrafficPermitted="true">
+        <trust-anchors>
+            <certificates src="system" />
+        </trust-anchors>
+    </base-config>
+</network-security-config>

android/app/src/test/java/dev/dettmer/simplenotes/ExampleUnitTest.kt

@@ -14,4 +14,4 @@ class ExampleUnitTest {
     fun addition_isCorrect() {
         assertEquals(4, 2 + 2)
     }
-}
+}

android/build.gradle.kts

@@ -2,4 +2,6 @@
 plugins {
     alias(libs.plugins.android.application) apply false
     alias(libs.plugins.kotlin.android) apply false
+    alias(libs.plugins.ktlint) apply false
+    alias(libs.plugins.detekt) apply false
 }

android/config/detekt/detekt.yml

@@ -0,0 +1,136 @@
+# ⚡ v1.3.1: detekt Configuration
+# Pragmatic rules for simple-notes-sync
+
+build:
+  maxIssues: 100  # Allow existing issues for v1.3.1 release, fix in v1.4.0
+  excludeCorrectable: false
+
+config:
+  validation: true
+  warningsAsErrors: false
+
+comments:
+  CommentOverPrivateProperty:
+    active: false
+  UndocumentedPublicClass:
+    active: false
+  UndocumentedPublicFunction:
+    active: false
+
+complexity:
+  ComplexCondition:
+    active: true
+    threshold: 5
+  CyclomaticComplexMethod:
+    active: true
+    threshold: 15
+    ignoreSingleWhenExpression: true
+  LargeClass:
+    active: true
+    threshold: 600  # Increased for WebDavSyncService
+  LongMethod:
+    active: true
+    threshold: 80  # Increased for sync methods
+  LongParameterList:
+    active: true
+    functionThreshold: 6
+    constructorThreshold: 7
+  NestedBlockDepth:
+    active: true
+    threshold: 5
+  TooManyFunctions:
+    active: true
+    thresholdInFiles: 25
+    thresholdInClasses: 25
+    thresholdInInterfaces: 20
+    thresholdInObjects: 20
+    thresholdInEnums: 10
+
+empty-blocks:
+  EmptyCatchBlock:
+    active: true
+    allowedExceptionNameRegex: "_|(ignore|expected).*"
+  EmptyFunctionBlock:
+    active: true
+    ignoreOverridden: true
+
+exceptions:
+  SwallowedException:
+    active: true
+    ignoredExceptionTypes:
+      - "InterruptedException"
+      - "MalformedURLException"
+      - "NumberFormatException"
+      - "ParseException"
+  TooGenericExceptionCaught:
+    active: true
+    exceptionNames:
+      - "Error"
+      - "Throwable"
+    allowedExceptionNameRegex: "_|(ignore|expected).*"
+
+naming:
+  FunctionNaming:
+    active: true
+    functionPattern: "[a-zA-Z][a-zA-Z0-9]*"
+  VariableNaming:
+    active: true
+    variablePattern: "[a-z][A-Za-z0-9]*"
+  PackageNaming:
+    active: true
+    packagePattern: "[a-z]+(\\.[a-z][A-Za-z0-9]*)*"
+
+performance:
+  SpreadOperator:
+    active: false  # Spread operator is fine in most cases
+
+potential-bugs:
+  CastToNullableType:
+    active: true
+  EqualsWithHashCodeExist:
+    active: true
+  UnconditionalJumpStatementInLoop:
+    active: true
+
+style:
+  ForbiddenComment:
+    active: true
+    comments:
+      - "FIXME:"
+      - "STOPSHIP:"
+    allowedPatterns: ""
+  MagicNumber:
+    active: true
+    ignoreNumbers:
+      - "-1"
+      - "0"
+      - "1"
+      - "2"
+      - "100"
+      - "1000"
+    ignoreHashCodeFunction: true
+    ignorePropertyDeclaration: true
+    ignoreLocalVariableDeclaration: true
+    ignoreAnnotation: true
+    ignoreEnums: true
+    ignoreRanges: true
+    ignoreExtensionFunctions: true
+  MaxLineLength:
+    active: true
+    maxLineLength: 120
+    excludePackageStatements: true
+    excludeImportStatements: true
+  ReturnCount:
+    active: true
+    max: 4
+    excludedFunctions: []
+    excludeLabeled: true
+    excludeReturnFromLambda: true
+    excludeGuardClauses: true
+  UnusedImports:
+    active: true
+  UnusedPrivateMember:
+    active: true
+    allowedNames: "_.*"
+  WildcardImport:
+    active: false  # Allow wildcard imports

android/gradle/libs.versions.toml

@@ -9,6 +9,8 @@ appcompat = "1.6.1"
 material = "1.10.0"
 activity = "1.8.0"
 constraintlayout = "2.1.4"
+ktlint = "12.1.0"
+detekt = "1.23.4"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -23,4 +25,6 @@ androidx-constraintlayout = { group = "androidx.constraintlayout", name = "const
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }
 kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }
+ktlint = { id = "org.jlleitschuh.gradle.ktlint", version.ref = "ktlint" }
+detekt = { id = "io.gitlab.arturbosch.detekt", version.ref = "detekt" }
 

android/gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Sat Dec 20 00:06:31 CET 2025
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionSha256Sum=20f1b1176237254a6fc204d8434196fa11a4cfb387567519c61556e8710aed78
 distributionUrl=https\://services.gradle.org/distributions/gradle-8.13-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true

android/gradlew

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 #
-# Copyright © 2015 the original authors.
+# Copyright © 2015-2021 the original authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -114,7 +114,7 @@ case "$( uname )" in                #(
   NONSTOP* )        nonstop=true ;;
 esac
 
-CLASSPATH="\\\"\\\""
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
 
 
 # Determine the Java command to use to start the JVM.
@@ -213,7 +213,7 @@ DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
         -classpath "$CLASSPATH" \
-        -jar "$APP_HOME/gradle/wrapper/gradle-wrapper.jar" \
+        org.gradle.wrapper.GradleWrapperMain \
         "$@"
 
 # Stop when "xargs" is not available.

android/gradlew.bat

@@ -1,94 +1,94 @@
-@rem
+@rem
-@rem Copyright 2015 the original author or authors.
+@rem Copyright 2015 the original author or authors.
-@rem
+@rem
-@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem Licensed under the Apache License, Version 2.0 (the "License");
-@rem you may not use this file except in compliance with the License.
+@rem you may not use this file except in compliance with the License.
-@rem You may obtain a copy of the License at
+@rem You may obtain a copy of the License at
-@rem
+@rem
-@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem      https://www.apache.org/licenses/LICENSE-2.0
-@rem
+@rem
-@rem Unless required by applicable law or agreed to in writing, software
+@rem Unless required by applicable law or agreed to in writing, software
-@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem distributed under the License is distributed on an "AS IS" BASIS,
-@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-@rem See the License for the specific language governing permissions and
+@rem See the License for the specific language governing permissions and
-@rem limitations under the License.
+@rem limitations under the License.
-@rem
+@rem
-@rem SPDX-License-Identifier: Apache-2.0
+@rem SPDX-License-Identifier: Apache-2.0
-@rem
+@rem
-
+
-@if "%DEBUG%"=="" @echo off
+@if "%DEBUG%"=="" @echo off
-@rem ##########################################################################
+@rem ##########################################################################
-@rem
+@rem
-@rem  Gradle startup script for Windows
+@rem  Gradle startup script for Windows
-@rem
+@rem
-@rem ##########################################################################
+@rem ##########################################################################
-
+
-@rem Set local scope for the variables with windows NT shell
+@rem Set local scope for the variables with windows NT shell
-if "%OS%"=="Windows_NT" setlocal
+if "%OS%"=="Windows_NT" setlocal
-
+
-set DIRNAME=%~dp0
+set DIRNAME=%~dp0
-if "%DIRNAME%"=="" set DIRNAME=.
+if "%DIRNAME%"=="" set DIRNAME=.
-@rem This is normally unused
+@rem This is normally unused
-set APP_BASE_NAME=%~n0
+set APP_BASE_NAME=%~n0
-set APP_HOME=%DIRNAME%
+set APP_HOME=%DIRNAME%
-
+
-@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
-for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
-
+
-@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
-set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
-
+
-@rem Find java.exe
+@rem Find java.exe
-if defined JAVA_HOME goto findJavaFromJavaHome
+if defined JAVA_HOME goto findJavaFromJavaHome
-
+
-set JAVA_EXE=java.exe
+set JAVA_EXE=java.exe
-%JAVA_EXE% -version >NUL 2>&1
+%JAVA_EXE% -version >NUL 2>&1
-if %ERRORLEVEL% equ 0 goto execute
+if %ERRORLEVEL% equ 0 goto execute
-
+
-echo. 1>&2
+echo. 1>&2
-echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
-echo. 1>&2
+echo. 1>&2
-echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
-echo location of your Java installation. 1>&2
+echo location of your Java installation. 1>&2
-
+
-goto fail
+goto fail
-
+
-:findJavaFromJavaHome
+:findJavaFromJavaHome
-set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_HOME=%JAVA_HOME:"=%
-set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
-
+
-if exist "%JAVA_EXE%" goto execute
+if exist "%JAVA_EXE%" goto execute
-
+
-echo. 1>&2
+echo. 1>&2
-echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
-echo. 1>&2
+echo. 1>&2
-echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
-echo location of your Java installation. 1>&2
+echo location of your Java installation. 1>&2
-
+
-goto fail
+goto fail
-
+
-:execute
+:execute
-@rem Setup the command line
+@rem Setup the command line
-
+
-set CLASSPATH=
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
-
+
-
+
-@rem Execute Gradle
+@rem Execute Gradle
-"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %*
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
-
+
-:end
+:end
-@rem End local scope for the variables with windows NT shell
+@rem End local scope for the variables with windows NT shell
-if %ERRORLEVEL% equ 0 goto mainEnd
+if %ERRORLEVEL% equ 0 goto mainEnd
-
+
-:fail
+:fail
-rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
-rem the _cmd.exe /c_ return code!
+rem the _cmd.exe /c_ return code!
-set EXIT_CODE=%ERRORLEVEL%
+set EXIT_CODE=%ERRORLEVEL%
-if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
-if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
-exit /b %EXIT_CODE%
+exit /b %EXIT_CODE%
-
+
-:mainEnd
+:mainEnd
-if "%OS%"=="Windows_NT" endlocal
+if "%OS%"=="Windows_NT" endlocal
-
+
-:omega
+:omega

android/key.properties.example

@@ -0,0 +1,21 @@
+# Android Signing Configuration
+# 
+# ANLEITUNG FÜR LOKALE BUILDS:
+# 1. Kopiere diese Datei nach "key.properties" (ohne .example)
+# 2. Fülle die Werte mit deinen echten Keystore-Daten aus
+# 3. Die key.properties Datei ist in .gitignore und wird NICHT committet
+#
+# WICHTIG: Diese Datei darf NIEMALS ins Git-Repository gelangen!
+# Sie enthält sensible Signing-Keys für die App-Veröffentlichung.
+
+# Pfad zum Keystore (relativ zum android/app Ordner)
+storeFile=simple-notes-release.jks
+
+# Keystore Password
+storePassword=DEIN_KEYSTORE_PASSWORD
+
+# Key Alias (meist "key0" oder ein selbst gewählter Name)
+keyAlias=DEIN_KEY_ALIAS
+
+# Key Password
+keyPassword=DEIN_KEY_PASSWORD

android/scripts/README.md

@@ -0,0 +1,192 @@
+# Android Build Scripts
+
+Nützliche Scripts für die lokale Entwicklung und Release-Erstellung.
+
+## 📜 Verfügbare Scripts
+
+### 1. `create-keystore.fish` - Neuen Release-Keystore erstellen
+
+**Wann verwenden:**
+- ✅ Erstmaliges Setup des Projekts
+- ✅ Keystore-Passwort vergessen
+- ✅ Keystore beschädigt oder verloren
+- ❌ **NICHT** verwenden, wenn bereits User existieren (macht alte APKs inkompatibel!)
+
+**Verwendung:**
+```bash
+cd /home/liq/gitProjects/simple-notes-sync/android
+./scripts/create-keystore.fish
+```
+
+**Das Script:**
+1. Erstellt einen neuen 4096-Bit RSA-Keystore
+2. Generiert `app/simple-notes-release.jks`
+3. Erstellt `key.properties` mit den Zugangsdaten
+4. Zeigt Base64-kodierten Keystore für GitHub Secrets
+5. Gibt SHA256-Fingerprint zur Verifikation aus
+
+**Output:**
+- ✅ `app/simple-notes-release.jks` - Der Keystore
+- ✅ `key.properties` - Lokale Signing-Konfiguration
+- 📋 GitHub Secrets zum Kopieren
+
+---
+
+### 2. `verify-secrets.fish` - GitHub Secrets & Keystore verifizieren
+
+**Wann verwenden:**
+- ✅ Nach `create-keystore.fish` zur Verifikation
+- ✅ Vor einem Release-Build zum Troubleshooting
+- ✅ Um zu prüfen ob alles korrekt konfiguriert ist
+
+**Verwendung:**
+```bash
+cd /home/liq/gitProjects/simple-notes-sync/android
+./scripts/verify-secrets.fish
+```
+
+**Das Script prüft:**
+- GitHub CLI Installation & Authentifizierung
+- Ob alle 4 erforderlichen GitHub Secrets gesetzt sind
+- Ob `key.properties` lokal existiert
+- Ob der Keystore existiert
+- Zeigt SHA256-Fingerprint des Keystores
+
+**Output:**
+- ✅ Status aller Secrets
+- ✅ Status der lokalen Konfiguration
+- 💡 Empfehlungen bei Problemen
+
+---
+
+### 3. `build-release-local.fish` - Lokal signierte Release-APKs bauen
+
+**Wann verwenden:**
+- ✅ Lokale Test-APKs erstellen, die mit Releases kompatibel sind
+- ✅ APKs vor dem GitHub Release testen
+- ✅ Schneller als GitHub Actions für Tests
+
+**Voraussetzung:**
+- `key.properties` muss existieren (via `create-keystore.fish` erstellt)
+
+**Verwendung:**
+```bash
+cd /home/liq/gitProjects/simple-notes-sync/android
+./scripts/build-release-local.fish
+```
+
+**Interaktive Auswahl:**
+1. Standard Flavor (empfohlen)
+2. F-Droid Flavor
+3. Beide Flavors
+
+**Output:**
+- `app/build/outputs/apk/standard/release/` - Signierte Standard APKs
+- `app/build/outputs/apk/fdroid/release/` - Signierte F-Droid APKs
+
+---
+
+## 🚀 Kompletter Workflow (von 0 auf Release)
+
+### Erstmaliges Setup
+
+```bash
+cd /home/liq/gitProjects/simple-notes-sync/android
+
+# 1. Keystore erstellen (mit automatischer GitHub Secrets-Konfiguration!)
+./scripts/create-keystore.fish
+# → Folge den Anweisungen, speichere die Passwörter!
+# → GitHub Secrets werden automatisch via GitHub CLI gesetzt
+
+# 2. Verifiziere die Konfiguration
+./scripts/verify-secrets.fish
+# → Prüft ob alle Secrets gesetzt sind
+# → Zeigt Keystore-Informationen
+
+# 3. Teste lokalen Build
+./scripts/build-release-local.fish
+# → Wähle "1" für Standard Flavor
+
+# 4. Verifiziere Signatur
+keytool -printcert -jarfile app/build/outputs/apk/standard/release/app-standard-universal-release.apk
+```
+
+### Vor jedem Release
+
+```bash
+# 1. Code committen und pushen
+git add .
+git commit -m "✨ Neue Features"
+git push origin main
+
+# 2. GitHub Actions erstellt automatisch Release
+# → Workflow läuft: .github/workflows/build-production-apk.yml
+# → Erstellt Release mit signierten APKs
+
+# Optional: Lokalen Test-Build vorher
+./scripts/build-release-local.fish
+```
+
+---
+
+## 🔐 Sicherheitshinweise
+
+### ⚠️ Diese Dateien NIEMALS committen:
+- `key.properties` - Enthält Keystore-Passwörter
+- `*.jks` / `*.keystore` - Der Keystore selbst
+- Beide sind bereits in `.gitignore`
+
+### ✅ Diese Werte sicher speichern:
+- Keystore-Passwort
+- Key-Alias
+- Key-Passwort
+- Base64-kodierter Keystore (für GitHub Secrets)
+
+**Empfehlung:** Nutze einen Passwort-Manager (Bitwarden, 1Password, etc.)
+
+---
+
+## 🛠️ Troubleshooting
+
+### "Keystore not found"
+```bash
+# Prüfe ob Keystore existiert
+ls -la app/simple-notes-release.jks
+
+# Falls nicht: Neu erstellen
+./scripts/create-keystore.fish
+```
+
+### "key.properties not found"
+```bash
+# Prüfe ob Datei existiert
+ls -la key.properties
+
+# Falls nicht: Keystore neu erstellen oder manuell anlegen
+./scripts/create-keystore.fish
+```
+
+### "Signature mismatch" beim App-Update
+**Problem:** Lokaler Build hat andere Signatur als GitHub Release
+
+**Ursache:** Unterschiedliche Keystores oder Passwörter
+
+**Lösung:**
+1. Vergleiche SHA256-Fingerprints:
+   ```bash
+   # Lokal
+   keytool -list -v -keystore app/simple-notes-release.jks
+   
+   # GitHub Release-APK
+   keytool -printcert -jarfile ~/Downloads/simple-notes-v1.1.0.apk
+   ```
+2. Müssen **identisch** sein!
+3. Falls nicht: GitHub Secrets mit lokaler `key.properties` synchronisieren
+
+---
+
+## 📚 Weitere Dokumentation
+
+- `../LOCAL_BUILDS.md` - Detaillierte Anleitung für lokale Builds
+- `../.github/workflows/build-production-apk.yml` - GitHub Actions Workflow
+- `../app/build.gradle.kts` - Build-Konfiguration

android/scripts/build-release-local.fish

@@ -0,0 +1,104 @@
+#!/usr/bin/env fish
+
+# Simple Notes Sync - Lokaler Release Build
+# Erstellt signierte APKs, die mit GitHub Release-APKs kompatibel sind
+
+set -l SCRIPT_DIR (dirname (status --current-filename))
+set -l ANDROID_DIR (realpath "$SCRIPT_DIR/..")
+set -l KEY_PROPERTIES "$ANDROID_DIR/key.properties"
+
+echo "🔨 Simple Notes Sync - Lokaler Release Build"
+echo ""
+
+# 1. Prüfe ob key.properties existiert
+if not test -f "$KEY_PROPERTIES"
+    echo "❌ Fehler: key.properties nicht gefunden!"
+    echo ""
+    echo "Bitte erstelle die Datei:"
+    echo "  cd $ANDROID_DIR"
+    echo "  cp key.properties.example key.properties"
+    echo ""
+    echo "Und fülle sie mit den echten Keystore-Daten aus."
+    echo "Siehe: android/LOCAL_BUILDS.md"
+    exit 1
+end
+
+# 2. Prüfe ob Keystore existiert
+set -l KEYSTORE "$ANDROID_DIR/app/simple-notes-release.jks"
+if not test -f "$KEYSTORE"
+    echo "❌ Fehler: Keystore nicht gefunden!"
+    echo "  Erwartet: $KEYSTORE"
+    exit 1
+end
+
+echo "✅ key.properties gefunden"
+echo "✅ Keystore gefunden"
+echo ""
+
+# 3. Build-Typ abfragen
+echo "Welchen Build möchtest du erstellen?"
+echo "  1) Standard Flavor (empfohlen)"
+echo "  2) F-Droid Flavor"
+echo "  3) Beide Flavors"
+echo ""
+read -P "Auswahl [1-3]: " -n 1 choice
+
+echo ""
+echo ""
+
+switch $choice
+    case 1
+        echo "🏗️  Baue Standard Release APKs..."
+        cd "$ANDROID_DIR"
+        ./gradlew assembleStandardRelease --no-daemon
+        
+        if test $status -eq 0
+            echo ""
+            echo "✅ Build erfolgreich!"
+            echo ""
+            echo "📦 APKs findest du hier:"
+            echo "  $ANDROID_DIR/app/build/outputs/apk/standard/release/"
+            ls -lh "$ANDROID_DIR/app/build/outputs/apk/standard/release/"*.apk
+        end
+        
+    case 2
+        echo "🏗️  Baue F-Droid Release APKs..."
+        cd "$ANDROID_DIR"
+        ./gradlew assembleFdroidRelease --no-daemon
+        
+        if test $status -eq 0
+            echo ""
+            echo "✅ Build erfolgreich!"
+            echo ""
+            echo "📦 APKs findest du hier:"
+            echo "  $ANDROID_DIR/app/build/outputs/apk/fdroid/release/"
+            ls -lh "$ANDROID_DIR/app/build/outputs/apk/fdroid/release/"*.apk
+        end
+        
+    case 3
+        echo "🏗️  Baue Standard + F-Droid Release APKs..."
+        cd "$ANDROID_DIR"
+        ./gradlew assembleStandardRelease assembleFdroidRelease --no-daemon
+        
+        if test $status -eq 0
+            echo ""
+            echo "✅ Build erfolgreich!"
+            echo ""
+            echo "📦 Standard APKs:"
+            echo "  $ANDROID_DIR/app/build/outputs/apk/standard/release/"
+            ls -lh "$ANDROID_DIR/app/build/outputs/apk/standard/release/"*.apk
+            echo ""
+            echo "📦 F-Droid APKs:"
+            echo "  $ANDROID_DIR/app/build/outputs/apk/fdroid/release/"
+            ls -lh "$ANDROID_DIR/app/build/outputs/apk/fdroid/release/"*.apk
+        end
+        
+    case '*'
+        echo "❌ Ungültige Auswahl"
+        exit 1
+end
+
+echo ""
+echo "💡 Tipp: Du kannst die APK per HTTP Server verteilen:"
+echo "   cd app/build/outputs/apk/standard/release"
+echo "   python3 -m http.server 8892"

android/scripts/create-keystore.fish

@@ -0,0 +1,279 @@
+#!/usr/bin/env fish
+
+# Simple Notes Sync - Keystore Generator
+# Erstellt einen neuen Release-Keystore für App-Signierung
+
+set -l SCRIPT_DIR (dirname (status --current-filename))
+set -l ANDROID_DIR (realpath "$SCRIPT_DIR/..")
+set -l KEYSTORE_PATH "$ANDROID_DIR/app/simple-notes-release.jks"
+set -l KEY_PROPERTIES "$ANDROID_DIR/key.properties"
+
+echo "🔐 Simple Notes Sync - Keystore Generator"
+echo ""
+echo "⚠️  WICHTIG: Dieser Keystore wird für alle zukünftigen App-Releases verwendet!"
+echo "    Speichere die Zugangsdaten sicher ab (z.B. in einem Passwort-Manager)."
+echo ""
+
+# Prüfe ob Keystore bereits existiert
+if test -f "$KEYSTORE_PATH"
+    echo "⚠️  Ein Keystore existiert bereits:"
+    echo "    $KEYSTORE_PATH"
+    echo ""
+    read -P "Möchtest du ihn überschreiben? (Dies macht alte APKs inkompatibel!) [j/N]: " -n 1 overwrite
+    echo ""
+    
+    if not string match -qi "j" $overwrite
+        echo "❌ Abgebrochen."
+        exit 1
+    end
+    
+    echo "🗑️  Lösche alten Keystore..."
+    rm "$KEYSTORE_PATH"
+end
+
+echo ""
+echo "📝 Bitte gib die folgenden Informationen ein:"
+echo ""
+
+# App-Informationen sammeln
+read -P "Dein Name (z.B. 'Max Mustermann'): " developer_name
+read -P "Organisation (z.B. 'dettmer.dev'): " organization
+read -P "Stadt: " city
+read -P "Land (z.B. 'DE'): " country
+
+echo ""
+echo "🔒 Keystore-Passwörter:"
+echo ""
+echo "Möchtest du sichere Passwörter automatisch generieren lassen?"
+read -P "[J/n]: " -n 1 auto_generate
+echo ""
+
+if string match -qi "n" $auto_generate
+    # Manuelle Passwort-Eingabe
+    echo ""
+    echo "📝 Manuelle Passwort-Eingabe:"
+    echo ""
+    
+    while true
+        read -sP "Keystore-Passwort: " keystore_password
+        echo ""
+        read -sP "Keystore-Passwort (Bestätigung): " keystore_password_confirm
+        echo ""
+        
+        if test "$keystore_password" = "$keystore_password_confirm"
+            break
+        else
+            echo "❌ Passwörter stimmen nicht überein. Bitte erneut eingeben."
+            echo ""
+        end
+    end
+    
+    while true
+        read -sP "Key-Passwort: " key_password
+        echo ""
+        read -sP "Key-Passwort (Bestätigung): " key_password_confirm
+        echo ""
+        
+        if test "$key_password" = "$key_password_confirm"
+            break
+        else
+            echo "❌ Passwörter stimmen nicht überein. Bitte erneut eingeben."
+            echo ""
+        end
+    end
+else
+    # Automatische Passwort-Generierung
+    echo ""
+    echo "🔐 Generiere sichere Passwörter (32 Zeichen, alphanumerisch)..."
+    
+    # Generiere sichere, zufällige Passwörter (alphanumerisch, 32 Zeichen)
+    set keystore_password (openssl rand -base64 32 | tr -d '/+=' | head -c 32)
+    set key_password (openssl rand -base64 32 | tr -d '/+=' | head -c 32)
+    
+    echo "✅ Passwörter generiert"
+    echo ""
+    echo "⚠️  WICHTIG: Speichere diese Passwörter jetzt in deinem Passwort-Manager!"
+    echo ""
+    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+    echo "Keystore-Passwort: $keystore_password"
+    echo "Key-Passwort:      $key_password"
+    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+    echo ""
+    read -P "Passwörter gespeichert? Drücke Enter zum Fortfahren..."
+end
+
+set -l key_alias "simple-notes-key"
+
+echo ""
+echo "🏗️  Erstelle Keystore..."
+echo ""
+
+# Keystore erstellen
+keytool -genkey \
+    -v \
+    -keystore "$KEYSTORE_PATH" \
+    -alias "$key_alias" \
+    -keyalg RSA \
+    -keysize 4096 \
+    -validity 10000 \
+    -storepass "$keystore_password" \
+    -keypass "$key_password" \
+    -dname "CN=$developer_name, OU=Simple Notes Sync, O=$organization, L=$city, C=$country"
+
+if test $status -ne 0
+    echo ""
+    echo "❌ Fehler beim Erstellen des Keystores!"
+    exit 1
+end
+
+echo ""
+echo "✅ Keystore erfolgreich erstellt!"
+echo ""
+
+# key.properties erstellen
+echo "📝 Erstelle key.properties..."
+echo "storeFile=simple-notes-release.jks" > "$KEY_PROPERTIES"
+echo "storePassword=$keystore_password" >> "$KEY_PROPERTIES"
+echo "keyAlias=$key_alias" >> "$KEY_PROPERTIES"
+echo "keyPassword=$key_password" >> "$KEY_PROPERTIES"
+
+echo "✅ key.properties erstellt"
+echo ""
+
+# Keystore-Info anzeigen
+echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+echo "📋 KEYSTORE-INFORMATIONEN - SICHER SPEICHERN!"
+echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+echo ""
+echo "Keystore-Pfad:      $KEYSTORE_PATH"
+echo "Key-Alias:          $key_alias"
+echo "Keystore-Passwort:  $keystore_password"
+echo "Key-Passwort:       $key_password"
+echo ""
+echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+echo ""
+
+# Base64-kodierten Keystore für GitHub Secrets
+echo "🔐 Base64-kodierter Keystore für GitHub Secrets:"
+echo ""
+set -l keystore_base64 (base64 -w 0 "$KEYSTORE_PATH")
+echo "$keystore_base64"
+echo ""
+echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+echo ""
+
+# GitHub Secrets konfigurieren
+echo "<22> GitHub Secrets konfigurieren..."
+echo ""
+
+# Prüfe ob GitHub CLI installiert ist
+if not command -v gh &> /dev/null
+    echo "⚠️  GitHub CLI (gh) nicht gefunden!"
+    echo ""
+    echo "📝 Manuelle Konfiguration erforderlich:"
+    echo ""
+    echo "1. Gehe zu: https://github.com/inentory69/simple-notes-sync/settings/secrets/actions"
+    echo "2. Erstelle/Aktualisiere folgende Secrets:"
+    echo ""
+    echo "   KEYSTORE_BASE64:"
+    echo "   $keystore_base64"
+    echo ""
+    echo "   KEYSTORE_PASSWORD:"
+    echo "   $keystore_password"
+    echo ""
+    echo "   KEY_ALIAS:"
+    echo "   $key_alias"
+    echo ""
+    echo "   KEY_PASSWORD:"
+    echo "   $key_password"
+    echo ""
+    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+    echo ""
+else
+    # GitHub CLI verfügbar - automatisch Secrets erstellen
+    echo "✅ GitHub CLI gefunden"
+    echo ""
+    
+    # Prüfe ob authentifiziert
+    if not gh auth status &> /dev/null
+        echo "⚠️  Nicht bei GitHub authentifiziert!"
+        echo ""
+        read -P "Möchtest du dich jetzt authentifizieren? [j/N]: " -n 1 do_auth
+        echo ""
+        
+        if string match -qi "j" $do_auth
+            gh auth login
+        else
+            echo "❌ Überspringe automatische Secret-Konfiguration"
+            echo ""
+            echo "📝 Manuelle Konfiguration erforderlich (siehe oben)"
+            echo ""
+            echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+            echo ""
+            return
+        end
+    end
+    
+    echo "🔐 Erstelle/Aktualisiere GitHub Secrets..."
+    echo ""
+    
+    set -l repo "inventory69/simple-notes-sync"
+    
+    # KEYSTORE_BASE64
+    echo "$keystore_base64" | gh secret set KEYSTORE_BASE64 --repo $repo
+    if test $status -eq 0
+        echo "✅ KEYSTORE_BASE64 gesetzt"
+    else
+        echo "❌ Fehler beim Setzen von KEYSTORE_BASE64"
+    end
+    
+    # KEYSTORE_PASSWORD
+    echo "$keystore_password" | gh secret set KEYSTORE_PASSWORD --repo $repo
+    if test $status -eq 0
+        echo "✅ KEYSTORE_PASSWORD gesetzt"
+    else
+        echo "❌ Fehler beim Setzen von KEYSTORE_PASSWORD"
+    end
+    
+    # KEY_ALIAS
+    echo "$key_alias" | gh secret set KEY_ALIAS --repo $repo
+    if test $status -eq 0
+        echo "✅ KEY_ALIAS gesetzt"
+    else
+        echo "❌ Fehler beim Setzen von KEY_ALIAS"
+    end
+    
+    # KEY_PASSWORD
+    echo "$key_password" | gh secret set KEY_PASSWORD --repo $repo
+    if test $status -eq 0
+        echo "✅ KEY_PASSWORD gesetzt"
+    else
+        echo "❌ Fehler beim Setzen von KEY_PASSWORD"
+    end
+    
+    echo ""
+    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+    echo ""
+    echo "✅ GitHub Secrets erfolgreich konfiguriert!"
+    echo ""
+    echo "🔍 Verifizieren:"
+    echo "   gh secret list --repo $repo"
+    echo ""
+    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+    echo ""
+end
+
+# Signatur-Fingerprint anzeigen
+echo "🔑 SHA256-Fingerprint (zur Verifikation):"
+keytool -list -v -keystore "$KEYSTORE_PATH" -storepass "$keystore_password" | grep "SHA256:"
+echo ""
+
+echo "✅ Setup abgeschlossen!"
+echo ""
+echo "💡 Nächste Schritte:"
+echo "   1. Speichere die obigen Informationen in einem Passwort-Manager"
+echo "   2. Konfiguriere die GitHub Secrets (siehe oben)"
+echo "   3. Teste den lokalen Build:"
+echo "      cd $ANDROID_DIR"
+echo "      ./gradlew assembleStandardRelease"
+echo ""

android/scripts/verify-secrets.fish

@@ -0,0 +1,150 @@
+#!/usr/bin/env fish
+
+# Simple Notes Sync - GitHub Secrets Verifier
+# Verifiziert ob die GitHub Secrets korrekt konfiguriert sind
+
+set -l repo "inventory69/simple-notes-sync"
+
+echo "🔍 GitHub Secrets Verifier"
+echo ""
+
+# Prüfe ob GitHub CLI installiert ist
+if not command -v gh &> /dev/null
+    echo "❌ GitHub CLI (gh) nicht gefunden!"
+    echo ""
+    echo "Installation:"
+    echo "  Arch Linux:  sudo pacman -S github-cli"
+    echo "  Ubuntu:      sudo apt install gh"
+    echo "  macOS:       brew install gh"
+    echo ""
+    exit 1
+end
+
+# Prüfe Authentifizierung
+if not gh auth status &> /dev/null
+    echo "❌ Nicht bei GitHub authentifiziert!"
+    echo ""
+    echo "Authentifizierung starten:"
+    echo "  gh auth login"
+    echo ""
+    exit 1
+end
+
+echo "✅ GitHub CLI authentifiziert"
+echo ""
+
+# Liste alle Secrets auf
+echo "📋 Konfigurierte Secrets für $repo:"
+echo ""
+gh secret list --repo $repo
+
+echo ""
+echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+echo ""
+
+# Prüfe ob alle erforderlichen Secrets vorhanden sind
+set -l required_secrets "KEYSTORE_BASE64" "KEYSTORE_PASSWORD" "KEY_ALIAS" "KEY_PASSWORD"
+set -l missing_secrets
+
+for secret in $required_secrets
+    if not gh secret list --repo $repo | grep -q "^$secret"
+        set -a missing_secrets $secret
+    end
+end
+
+if test (count $missing_secrets) -gt 0
+    echo "❌ Fehlende Secrets:"
+    for secret in $missing_secrets
+        echo "   - $secret"
+    end
+    echo ""
+    echo "💡 Tipp: Führe create-keystore.fish aus, um die Secrets zu erstellen"
+else
+    echo "✅ Alle erforderlichen Secrets sind konfiguriert!"
+    echo ""
+    echo "Required Secrets:"
+    for secret in $required_secrets
+        echo "   ✓ $secret"
+    end
+end
+
+echo ""
+echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+echo ""
+
+# Prüfe ob key.properties lokal existiert
+set -l SCRIPT_DIR (dirname (status --current-filename))
+set -l ANDROID_DIR (realpath "$SCRIPT_DIR/..")
+set -l KEY_PROPERTIES "$ANDROID_DIR/key.properties"
+
+if test -f "$KEY_PROPERTIES"
+    echo "✅ Lokale key.properties gefunden: $KEY_PROPERTIES"
+    echo ""
+    echo "📋 Inhalt (Passwörter verborgen):"
+    cat "$KEY_PROPERTIES" | sed 's/\(Password=\).*/\1***HIDDEN***/g'
+else
+    echo "⚠️  Lokale key.properties nicht gefunden: $KEY_PROPERTIES"
+    echo ""
+    echo "💡 Tipp: Führe create-keystore.fish aus, um sie zu erstellen"
+end
+
+echo ""
+echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+echo ""
+
+# Prüfe ob Keystore existiert
+set -l KEYSTORE "$ANDROID_DIR/app/simple-notes-release.jks"
+if test -f "$KEYSTORE"
+    echo "✅ Keystore gefunden: $KEYSTORE"
+    
+    # Zeige Keystore-Info (wenn key.properties existiert)
+    if test -f "$KEY_PROPERTIES"
+        set -l store_password (grep "storePassword=" "$KEY_PROPERTIES" | cut -d'=' -f2)
+        
+        echo ""
+        echo "🔑 Keystore-Informationen:"
+        keytool -list -v -keystore "$KEYSTORE" -storepass "$store_password" 2>/dev/null | grep -E "(Alias|Creation date|Valid|SHA256)" | head -10
+    end
+else
+    echo "⚠️  Keystore nicht gefunden: $KEYSTORE"
+    echo ""
+    echo "💡 Tipp: Führe create-keystore.fish aus, um ihn zu erstellen"
+end
+
+echo ""
+echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
+echo ""
+
+# Zusammenfassung
+set -l issues 0
+
+if test (count $missing_secrets) -gt 0
+    set issues (math $issues + 1)
+end
+
+if not test -f "$KEY_PROPERTIES"
+    set issues (math $issues + 1)
+end
+
+if not test -f "$KEYSTORE"
+    set issues (math $issues + 1)
+end
+
+if test $issues -eq 0
+    echo "🎉 Alles konfiguriert! Du kannst jetzt Releases erstellen."
+    echo ""
+    echo "🚀 Nächste Schritte:"
+    echo "   1. Lokalen Build testen:"
+    echo "      ./scripts/build-release-local.fish"
+    echo ""
+    echo "   2. Code committen und pushen:"
+    echo "      git push origin main"
+    echo ""
+    echo "   3. GitHub Actions erstellt automatisch Release"
+else
+    echo "⚠️  $issues Problem(e) gefunden - siehe oben"
+    echo ""
+    echo "💡 Lösung: Führe create-keystore.fish aus"
+end
+
+echo ""

docs/BACKUP.en.md

@@ -0,0 +1,324 @@
+# Backup & Restore 💾
+
+**🌍 Languages:** [Deutsch](BACKUP.md) · **English**
+
+> Secure your notes locally - independent from the server
+
+---
+
+## 📋 Overview
+
+The backup system works **completely offline** and independent from the WebDAV server. Perfect for:
+- 📥 Regular backups
+- 📤 Migration to new server
+- 🔄 Recovery after data loss
+- 💾 Archiving old notes
+
+---
+
+## 📥 Create Backup
+
+### Step-by-Step
+
+1. **Open settings** (⚙️ icon top right)
+2. **Find "Backup & Restore"** section
+3. **Tap "📥 Create backup"**
+4. **Choose location:**
+   - 📁 Downloads
+   - 💳 SD card
+   - ☁️ Cloud folder (Nextcloud, Google Drive, etc.)
+   - 📧 Email as attachment
+5. **Done!** Backup file is saved
+
+### File Format
+
+**Filename:** `simplenotes_backup_YYYY-MM-DD_HHmmss.json`
+
+**Example:** `simplenotes_backup_2026-01-05_143022.json`
+
+**Content:**
+```json
+{
+  "version": "1.2.1",
+  "exported_at": "2026-01-05T14:30:22Z",
+  "notes_count": 42,
+  "notes": [
+    {
+      "id": "abc-123-def",
+      "title": "Shopping List",
+      "content": "Milk\nBread\nCheese",
+      "createdAt": 1704467422000,
+      "updatedAt": 1704467422000
+    }
+  ]
+}
+```
+
+**Format details:**
+- ✅ Human-readable (formatted JSON)
+- ✅ All data included (title, content, IDs, timestamps)
+- ✅ Version info for compatibility
+- ✅ Note count for validation
+
+---
+
+## 📤 Restore Backup
+
+### 3 Restore Modes
+
+#### 1. Merge ⭐ _Recommended_
+
+**What happens:**
+- ✅ New notes from backup are added
+- ✅ Existing notes remain unchanged
+- ✅ No data loss
+
+**When to use:**
+- Import backup from another device
+- Recover old notes
+- Restore accidentally deleted notes
+
+**Example:**
+```
+App:    [Note A, Note B, Note C]
+Backup: [Note A, Note D, Note E]
+Result: [Note A, Note B, Note C, Note D, Note E]
+```
+
+#### 2. Replace
+
+**What happens:**
+- ❌ ALL existing notes are deleted
+- ✅ Backup notes are imported
+- ⚠️ Irreversible (except through auto-backup)
+
+**When to use:**
+- Server migration (complete restart)
+- Return to old backup state
+- App reinstallation
+
+**Example:**
+```
+App:    [Note A, Note B, Note C]
+Backup: [Note X, Note Y]
+Result: [Note X, Note Y]
+```
+
+**⚠️ Warning:** Automatic safety backup is created!
+
+#### 3. Overwrite Duplicates
+
+**What happens:**
+- ✅ New notes from backup are added
+- 🔄 On ID conflicts, backup wins
+- ✅ Other notes remain unchanged
+
+**When to use:**
+- Backup is newer than app data
+- Import desktop changes
+- Conflict resolution
+
+**Example:**
+```
+App:    [Note A (v1), Note B, Note C]
+Backup: [Note A (v2), Note D]
+Result: [Note A (v2), Note B, Note C, Note D]
+```
+
+### Restore Process
+
+1. **Settings** → **"📤 Restore from file"**
+2. **Select backup file** (`.json`)
+3. **Choose mode:**
+   - 🔵 Merge _(Default)_
+   - 🟡 Overwrite duplicates
+   - 🔴 Replace _(Caution!)_
+4. **Confirm** - Automatic safety backup is created
+5. **Wait** - Import runs
+6. **Done!** - Success message with number of imported notes
+
+---
+
+## 🛡️ Automatic Safety Backup
+
+**Before every restore:**
+- ✅ Automatic backup is created
+- 📁 Saved in: `Android/data/dev.dettmer.simplenotes/files/`
+- 🏷️ Filename: `auto_backup_before_restore_YYYY-MM-DD_HHmmss.json`
+- ⏱️ Timestamp: Right before restore
+
+**Why?**
+- Protection against accidental "Replace"
+- Ability to undo
+- Double security
+
+**Access via file manager:**
+```
+/Android/data/dev.dettmer.simplenotes/files/auto_backup_before_restore_*.json
+```
+
+---
+
+## 💡 Best Practices
+
+### Backup Strategy
+
+#### Regular Backups
+```
+Daily:   ❌ Too often (server sync is enough)
+Weekly:  ✅ Recommended for important notes
+Monthly: ✅ Archiving
+Before updates: ✅ Safety
+```
+
+#### 3-2-1 Rule
+1. **3 copies** - Original + 2 backups
+2. **2 media** - e.g., SD card + cloud
+3. **1 offsite** - e.g., cloud storage
+
+### Backup Locations
+
+**Local (fast):**
+- 📱 Internal storage / Downloads
+- 💳 SD card
+- 🖥️ PC (via USB)
+
+**Cloud (secure):**
+- ☁️ Nextcloud (self-hosted)
+- 📧 Email to yourself
+- 🗄️ Syncthing (sync between devices)
+
+**⚠️ Avoid:**
+- ❌ Google Drive / Dropbox (privacy)
+- ❌ Only one copy
+- ❌ Only on server (if server fails)
+
+---
+
+## 🔧 Advanced Usage
+
+### Edit Backup File
+
+The `.json` file can be edited with any text editor:
+
+1. **Open with:** VS Code, Notepad++, nano
+2. **Add/remove notes**
+3. **Change title/content**
+4. **Adjust IDs** (for migration)
+5. **Save** and import to app
+
+**⚠️ Important:**
+- Keep valid JSON format
+- IDs must be unique (UUIDs)
+- Timestamps in milliseconds (Unix Epoch)
+
+### Bulk Import
+
+Merge multiple backups:
+
+1. Import backup 1 (Mode: Merge)
+2. Import backup 2 (Mode: Merge)
+3. Import backup 3 (Mode: Merge)
+4. Result: All notes combined
+
+### Server Migration
+
+Step-by-step:
+
+1. **Create backup** on old server
+2. **Set up new server** (see [QUICKSTART.en.md](QUICKSTART.en.md))
+3. **Change server URL** in app settings
+4. **Restore backup** (Mode: Replace)
+5. **Test sync** - All notes on new server
+
+---
+
+## ❌ Troubleshooting
+
+### "Invalid backup file"
+
+**Causes:**
+- Corrupt JSON file
+- Wrong file extension (must be `.json`)
+- Incompatible app version
+
+**Solution:**
+1. Check JSON file with validator (e.g., jsonlint.com)
+2. Verify file extension
+3. Create backup with current app version
+
+### "No permission to save"
+
+**Causes:**
+- Storage permission missing
+- Write-protected folder
+
+**Solution:**
+1. Android: Settings → Apps → Simple Notes → Permissions
+2. Activate "Storage"
+3. Choose different location
+
+### "Import failed"
+
+**Causes:**
+- Not enough storage space
+- Corrupt backup file
+- App crash during import
+
+**Solution:**
+1. Free up storage space
+2. Create new backup file
+3. Restart app and try again
+
+---
+
+## 🔒 Security & Privacy
+
+### Data Protection
+- ✅ **Locally stored** - No cloud upload without your action
+- ✅ **No encryption** - Plain text format for readability
+- ⚠️ **Sensitive data?** - Encrypt backup file yourself (e.g., 7-Zip with password)
+
+### Recommendations
+- 🔐 Store backup files in encrypted container
+- 🗑️ Regularly delete old backups
+- 📧 Don't send via unencrypted email
+- ☁️ Use self-hosted cloud (Nextcloud)
+
+---
+
+## 📊 Technical Details
+
+### Format Specification
+
+**JSON structure:**
+```json
+{
+  "version": "string",        // App version at export
+  "exported_at": "ISO8601",   // Export timestamp
+  "notes_count": number,      // Number of notes
+  "notes": [
+    {
+      "id": "UUID",           // Unique ID
+      "title": "string",      // Note title
+      "content": "string",    // Note content
+      "createdAt": number,    // Unix timestamp (ms)
+      "updatedAt": number     // Unix timestamp (ms)
+    }
+  ]
+}
+```
+
+### Compatibility
+- ✅ v1.2.0+ - Fully compatible
+- ⚠️ v1.1.x - Basic functions (without auto-backup)
+- ❌ v1.0.x - Not supported
+
+---
+
+**📚 See also:**
+- [QUICKSTART.en.md](../QUICKSTART.en.md) - App installation and setup
+- [FEATURES.en.md](FEATURES.en.md) - Complete feature list
+- [DESKTOP.en.md](DESKTOP.en.md) - Desktop integration with Markdown
+
+**Last update:** v1.2.1 (2026-01-05)

docs/BACKUP.md

@@ -0,0 +1,324 @@
+# Backup & Wiederherstellung 💾
+
+**🌍 Languages:** **Deutsch** · [English](BACKUP.en.md)
+
+> Sichere deine Notizen lokal - unabhängig vom Server
+
+---
+
+## 📋 Übersicht
+
+Das Backup-System funktioniert **komplett offline** und unabhängig vom WebDAV-Server. Perfekt für:
+- 📥 Regelmäßige Sicherungen
+- 📤 Migration zu neuem Server
+- 🔄 Wiederherstellung nach Datenverlust
+- 💾 Archivierung alter Notizen
+
+---
+
+## 📥 Backup erstellen
+
+### Schritt-für-Schritt
+
+1. **Einstellungen öffnen** (⚙️ Icon oben rechts)
+2. **"Backup & Wiederherstellung"** Section finden
+3. **"📥 Backup erstellen"** antippen
+4. **Speicherort wählen:**
+   - 📁 Downloads
+   - 💳 SD-Karte
+   - ☁️ Cloud-Ordner (Nextcloud, Google Drive, etc.)
+   - 📧 E-Mail als Anhang
+5. **Fertig!** Backup-Datei ist gespeichert
+
+### Dateiformat
+
+**Dateiname:** `simplenotes_backup_YYYY-MM-DD_HHmmss.json`
+
+**Beispiel:** `simplenotes_backup_2026-01-05_143022.json`
+
+**Inhalt:**
+```json
+{
+  "version": "1.2.1",
+  "exported_at": "2026-01-05T14:30:22Z",
+  "notes_count": 42,
+  "notes": [
+    {
+      "id": "abc-123-def",
+      "title": "Einkaufsliste",
+      "content": "Milch\nBrot\nKäse",
+      "createdAt": 1704467422000,
+      "updatedAt": 1704467422000
+    }
+  ]
+}
+```
+
+**Format-Details:**
+- ✅ Menschenlesbar (formatiertes JSON)
+- ✅ Alle Daten inklusive (Titel, Inhalt, IDs, Timestamps)
+- ✅ Versions-Info für Kompatibilität
+- ✅ Anzahl der Notizen für Validierung
+
+---
+
+## 📤 Backup wiederherstellen
+
+### 3 Wiederherstellungs-Modi
+
+#### 1. Zusammenführen (Merge) ⭐ _Empfohlen_
+
+**Was passiert:**
+- ✅ Neue Notizen aus Backup werden hinzugefügt
+- ✅ Bestehende Notizen bleiben unverändert
+- ✅ Keine Datenverluste
+
+**Wann nutzen:**
+- Backup von anderem Gerät einspielen
+- Alte Notizen zurückholen
+- Versehentlich gelöschte Notizen wiederherstellen
+
+**Beispiel:**
+```
+App:    [Notiz A, Notiz B, Notiz C]
+Backup: [Notiz A, Notiz D, Notiz E]
+Ergebnis: [Notiz A, Notiz B, Notiz C, Notiz D, Notiz E]
+```
+
+#### 2. Ersetzen (Replace)
+
+**Was passiert:**
+- ❌ ALLE bestehenden Notizen werden gelöscht
+- ✅ Backup-Notizen werden importiert
+- ⚠️ Unwiderruflich (außer durch Auto-Backup)
+
+**Wann nutzen:**
+- Server-Wechsel (kompletter Neustart)
+- Zurück zu altem Backup-Stand
+- App-Neuinstallation
+
+**Beispiel:**
+```
+App:    [Notiz A, Notiz B, Notiz C]
+Backup: [Notiz X, Notiz Y]
+Ergebnis: [Notiz X, Notiz Y]
+```
+
+**⚠️ Warnung:** Automatisches Sicherheits-Backup wird erstellt!
+
+#### 3. Duplikate überschreiben (Overwrite)
+
+**Was passiert:**
+- ✅ Neue Notizen aus Backup werden hinzugefügt
+- 🔄 Bei ID-Konflikten gewinnt das Backup
+- ✅ Andere Notizen bleiben unverändert
+
+**Wann nutzen:**
+- Backup ist neuer als App-Daten
+- Desktop-Änderungen einspielen
+- Konflikt-Auflösung
+
+**Beispiel:**
+```
+App:    [Notiz A (v1), Notiz B, Notiz C]
+Backup: [Notiz A (v2), Notiz D]
+Ergebnis: [Notiz A (v2), Notiz B, Notiz C, Notiz D]
+```
+
+### Wiederherstellungs-Prozess
+
+1. **Einstellungen** → **"📤 Aus Datei wiederherstellen"**
+2. **Backup-Datei auswählen** (`.json`)
+3. **Modus wählen:**
+   - 🔵 Zusammenführen _(Standard)_
+   - 🟡 Duplikate überschreiben
+   - 🔴 Ersetzen _(Vorsicht!)_
+4. **Bestätigen** - Automatisches Sicherheits-Backup wird erstellt
+5. **Warten** - Import läuft
+6. **Fertig!** - Erfolgsmeldung mit Anzahl importierter Notizen
+
+---
+
+## 🛡️ Automatisches Sicherheits-Backup
+
+**Vor jeder Wiederherstellung:**
+- ✅ Automatisches Backup wird erstellt
+- 📁 Gespeichert in: `Android/data/dev.dettmer.simplenotes/files/`
+- 🏷️ Dateiname: `auto_backup_before_restore_YYYY-MM-DD_HHmmss.json`
+- ⏱️ Zeitstempel: Direkt vor Wiederherstellung
+
+**Warum?**
+- Schutz vor versehentlichem "Ersetzen"
+- Möglichkeit zum Rückgängigmachen
+- Doppelte Sicherheit
+
+**Zugriff via Dateimanager:**
+```
+/Android/data/dev.dettmer.simplenotes/files/auto_backup_before_restore_*.json
+```
+
+---
+
+## 💡 Best Practices
+
+### Backup-Strategie
+
+#### Regelmäßige Backups
+```
+Täglich:   ❌ Zu oft (Server-Sync reicht)
+Wöchentlich: ✅ Empfohlen für wichtige Notizen
+Monatlich:  ✅ Archivierung
+Vor Updates: ✅ Sicherheit
+```
+
+#### 3-2-1 Regel
+1. **3 Kopien** - Original + 2 Backups
+2. **2 Medien** - z.B. SD-Karte + Cloud
+3. **1 Offsite** - z.B. Cloud-Speicher
+
+### Backup-Speicherorte
+
+**Lokal (schnell):**
+- 📱 Internal Storage / Downloads
+- 💳 SD-Karte
+- 🖥️ PC (via USB)
+
+**Cloud (sicher):**
+- ☁️ Nextcloud (Self-Hosted)
+- 📧 E-Mail an sich selbst
+- 🗄️ Syncthing (Sync zwischen Geräten)
+
+**⚠️ Vermeiden:**
+- ❌ Google Drive / Dropbox (Privacy)
+- ❌ Nur eine Kopie
+- ❌ Nur auf Server (wenn Server ausfällt)
+
+---
+
+## 🔧 Erweiterte Nutzung
+
+### Backup-Datei bearbeiten
+
+Die `.json` Datei kann mit jedem Texteditor bearbeitet werden:
+
+1. **Öffnen mit:** VS Code, Notepad++, nano
+2. **Notizen hinzufügen/entfernen**
+3. **Titel/Inhalt ändern**
+4. **IDs anpassen** (für Migration)
+5. **Speichern** und in App importieren
+
+**⚠️ Wichtig:**
+- Valides JSON-Format behalten
+- IDs müssen eindeutig sein (UUIDs)
+- Timestamps in Millisekunden (Unix Epoch)
+
+### Bulk-Import
+
+Mehrere Backups zusammenführen:
+
+1. Backup 1 importieren (Modus: Zusammenführen)
+2. Backup 2 importieren (Modus: Zusammenführen)
+3. Backup 3 importieren (Modus: Zusammenführen)
+4. Ergebnis: Alle Notizen vereint
+
+### Server-Migration
+
+Schritt-für-Schritt:
+
+1. **Backup erstellen** auf altem Server
+2. **Neuen Server einrichten** (siehe [QUICKSTART.md](QUICKSTART.md))
+3. **Server-URL ändern** in App-Einstellungen
+4. **Backup wiederherstellen** (Modus: Ersetzen)
+5. **Sync testen** - Alle Notizen auf neuem Server
+
+---
+
+## ❌ Fehlerbehebung
+
+### "Backup-Datei ungültig"
+
+**Ursachen:**
+- Korrupte JSON-Datei
+- Falsche Datei-Endung (muss `.json` sein)
+- Inkompatible App-Version
+
+**Lösung:**
+1. JSON-Datei mit Validator prüfen (z.B. jsonlint.com)
+2. Dateiendung überprüfen
+3. Backup mit aktueller App-Version erstellen
+
+### "Keine Berechtigung zum Speichern"
+
+**Ursachen:**
+- Speicher-Berechtigung fehlt
+- Schreibgeschützter Ordner
+
+**Lösung:**
+1. Android: Einstellungen → Apps → Simple Notes → Berechtigungen
+2. "Speicher" aktivieren
+3. Anderen Speicherort wählen
+
+### "Import fehlgeschlagen"
+
+**Ursachen:**
+- Zu wenig Speicherplatz
+- Korrupte Backup-Datei
+- App-Crash während Import
+
+**Lösung:**
+1. Speicherplatz freigeben
+2. Backup-Datei neu erstellen
+3. App neu starten und erneut importieren
+
+---
+
+## 🔒 Sicherheit & Privacy
+
+### Daten-Schutz
+- ✅ **Lokal gespeichert** - Kein Cloud-Upload ohne deine Aktion
+- ✅ **Keine Verschlüsselung** - Klartextformat für Lesbarkeit
+- ⚠️ **Sensible Daten?** - Backup-Datei selbst verschlüsseln (z.B. 7-Zip mit Passwort)
+
+### Empfehlungen
+- 🔐 Backup-Dateien in verschlüsseltem Container speichern
+- 🗑️ Alte Backups regelmäßig löschen
+- 📧 Nicht per unverschlüsselter E-Mail versenden
+- ☁️ Self-Hosted Cloud nutzen (Nextcloud)
+
+---
+
+## 📊 Technische Details
+
+### Format-Spezifikation
+
+**JSON-Struktur:**
+```json
+{
+  "version": "string",        // App-Version beim Export
+  "exported_at": "ISO8601",   // Zeitstempel des Exports
+  "notes_count": number,      // Anzahl der Notizen
+  "notes": [
+    {
+      "id": "UUID",           // Eindeutige ID
+      "title": "string",      // Notiz-Titel
+      "content": "string",    // Notiz-Inhalt
+      "createdAt": number,    // Unix Timestamp (ms)
+      "updatedAt": number     // Unix Timestamp (ms)
+    }
+  ]
+}
+```
+
+### Kompatibilität
+- ✅ v1.2.0+ - Vollständig kompatibel
+- ⚠️ v1.1.x - Grundfunktionen (ohne Auto-Backup)
+- ❌ v1.0.x - Nicht unterstützt
+
+---
+
+**📚 Siehe auch:**
+- [QUICKSTART.md](../QUICKSTART.md) - App-Installation und Einrichtung
+- [FEATURES.md](FEATURES.md) - Vollständige Feature-Liste
+- [DESKTOP.md](DESKTOP.md) - Desktop-Integration mit Markdown
+
+**Letzte Aktualisierung:** v1.2.1 (2026-01-05)

docs/DESKTOP.en.md

@@ -0,0 +1,505 @@
+# Desktop Integration 🖥️
+
+**🌍 Languages:** [Deutsch](DESKTOP.md) · **English**
+
+> Edit your notes with any Markdown editor on desktop
+
+---
+
+## 📋 Overview
+
+Desktop integration allows you to edit notes on PC/Mac:
+- 📝 Any Markdown editor works
+- 🔄 Automatic synchronization via WebDAV
+- 💾 Dual-format: JSON (master) + Markdown (mirror)
+- ⚡ Last-Write-Wins conflict resolution
+
+---
+
+## 🎯 Why Markdown?
+
+### Dual-Format Architecture
+
+```
+┌─────────────────────────────────────┐
+│         Android App                 │
+│                                     │
+│  ┌──────────┐      ┌─────────────┐ │
+│  │   JSON   │ ──→  │  Markdown   │ │
+│  │ (Master) │      │  (Mirror)   │ │
+│  └──────────┘      └─────────────┘ │
+└────────┬────────────────┬───────────┘
+         │                │
+         ↓                ↓
+    WebDAV Server
+         │                │
+    ┌────┴────┐      ┌────┴──────┐
+    │ /notes/ │      │ /notes-md/│
+    │ *.json  │      │ *.md      │
+    └─────────┘      └───────────┘
+         ↑                ↑
+         │                │
+    ┌────┴────────────────┴───────────┐
+    │      Desktop Editor              │
+    │  (VS Code, Typora, etc.)         │
+    └──────────────────────────────────┘
+```
+
+### Advantages
+
+**JSON (Master):**
+- ✅ Reliable and fast
+- ✅ Structured data (IDs, timestamps)
+- ✅ Primary sync mechanism
+- ✅ Always active
+
+**Markdown (Mirror):**
+- ✅ Human-readable
+- ✅ Desktop editor compatible
+- ✅ Syntax highlighting
+- ✅ Optionally activatable
+
+---
+
+## 🚀 Quick Start
+
+### 1. First Synchronization
+
+**Important:** Perform a sync FIRST before activating desktop integration!
+
+1. **Set up app** (see [QUICKSTART.en.md](QUICKSTART.en.md))
+2. **Test server connection**
+3. **Create first note**
+4. **Synchronize** (pull-to-refresh or auto-sync)
+5. ✅ Server automatically creates `/notes/` and `/notes-md/` folders
+
+### 2. Activate Desktop Integration
+
+1. **Settings** → **Desktop Integration**
+2. **Toggle ON**
+3. **Initial export starts** - Shows progress (X/Y)
+4. ✅ All existing notes are exported as `.md`
+
+### 3. Mount WebDAV as Network Drive
+
+#### Windows
+
+```
+1. Open Explorer
+2. Right-click on "This PC"
+3. "Map network drive"
+4. Enter URL: http://YOUR-SERVER:8080/notes-md/
+5. Username: noteuser
+6. Password: (your WebDAV password)
+7. Drive letter: Z:\ (or any)
+8. Done!
+```
+
+**Access:** `Z:\` in Explorer
+
+#### macOS
+
+```
+1. Open Finder
+2. Menu "Go" → "Connect to Server" (⌘K)
+3. Server address: http://YOUR-SERVER:8080/notes-md/
+4. Connect
+5. Username: noteuser
+6. Password: (your WebDAV password)
+7. Done!
+```
+
+**Access:** Finder → Network → notes-md
+
+#### Linux (GNOME)
+
+```
+1. Open Files / Nautilus
+2. "Other Locations"
+3. "Connect to Server"
+4. Server address: dav://YOUR-SERVER:8080/notes-md/
+5. Username: noteuser
+6. Password: (your WebDAV password)
+7. Done!
+```
+
+**Access:** `/run/user/1000/gvfs/dav:host=...`
+
+#### Linux (davfs2 - permanent)
+
+```bash
+# Installation
+sudo apt install davfs2
+
+# Create mount point
+sudo mkdir -p /mnt/notes-md
+
+# Mount once
+sudo mount -t davfs http://YOUR-SERVER:8080/notes-md/ /mnt/notes-md
+
+# Permanent in /etc/fstab
+echo "http://YOUR-SERVER:8080/notes-md/ /mnt/notes-md davfs rw,user,noauto 0 0" | sudo tee -a /etc/fstab
+```
+
+**Access:** `/mnt/notes-md/`
+
+---
+
+## 📝 Markdown Editors
+
+### Recommended Editors
+
+#### 1. VS Code ⭐ _Recommended_
+
+**Advantages:**
+- ✅ Free & open source
+- ✅ Markdown preview (Ctrl+Shift+V)
+- ✅ Syntax highlighting
+- ✅ Git integration
+- ✅ Extensions (spell check, etc.)
+
+**Setup:**
+```
+1. Install VS Code
+2. Mount WebDAV drive
+3. Open folder: Z:\notes-md\ (Windows) or /mnt/notes-md (Linux)
+4. Done! Edit Markdown files
+```
+
+**Extensions (optional):**
+- `Markdown All in One` - Shortcuts & preview
+- `Markdown Preview Enhanced` - Better preview
+- `Code Spell Checker` - Spell checking
+
+#### 2. Typora
+
+**Advantages:**
+- ✅ WYSIWYG Markdown editor
+- ✅ Minimalist design
+- ✅ Live preview
+- ⚠️ Paid (~15€)
+
+**Setup:**
+```
+1. Install Typora
+2. Mount WebDAV
+3. Open folder in Typora
+4. Edit notes
+```
+
+#### 3. Notepad++
+
+**Advantages:**
+- ✅ Lightweight
+- ✅ Fast
+- ✅ Syntax highlighting
+- ⚠️ No Markdown preview
+
+**Setup:**
+```
+1. Install Notepad++
+2. Mount WebDAV
+3. Open files directly
+```
+
+#### 4. Obsidian
+
+**Advantages:**
+- ✅ Second brain philosophy
+- ✅ Graph view for links
+- ✅ Many plugins
+- ⚠️ Sync conflicts possible (2 masters)
+
+**Setup:**
+```
+1. Install Obsidian
+2. Open WebDAV as vault
+3. Caution: Obsidian creates own metadata!
+```
+
+**⚠️ Not recommended:** Can alter frontmatter
+
+---
+
+## 📄 Markdown File Format
+
+### Structure
+
+Each note is exported as `.md` file with YAML frontmatter:
+
+```markdown
+---
+id: abc-123-def-456
+created: 2026-01-05T14:30:22Z
+updated: 2026-01-05T14:30:22Z
+tags: []
+---
+
+# Note Title
+
+Note content here...
+```
+
+### Frontmatter Fields
+
+| Field | Type | Description | Required |
+|-------|------|-------------|----------|
+| `id` | UUID | Unique note ID | ✅ Yes |
+| `created` | ISO8601 | Creation date | ✅ Yes |
+| `updated` | ISO8601 | Modification date | ✅ Yes |
+| `tags` | Array | Tags (future) | ❌ No |
+
+### Filenames
+
+**Sanitization rules:**
+```
+Title: "My Shopping List 🛒"
+→ Filename: "My_Shopping_List.md"
+
+Removed:
+- Emojis: 🛒 → removed
+- Special chars: / \ : * ? " < > | → removed
+- Multiple spaces → single space
+- Spaces → underscore _
+```
+
+**Examples:**
+```
+"Meeting Notes 2026" → "Meeting_Notes_2026.md"
+"To-Do: Project" → "To-Do_Project.md"
+"Vacation ☀️" → "Vacation.md"
+```
+
+---
+
+## 🔄 Synchronization
+
+### Workflow: Android → Desktop
+
+1. **Create/edit note in app**
+2. **Run sync** (auto or manual)
+3. **JSON is uploaded** (`/notes/abc-123.json`)
+4. **Markdown is exported** (`/notes-md/Note_Title.md`) _(only if Desktop Integration ON)_
+5. **Desktop editor shows changes** (after refresh)
+
+### Workflow: Desktop → Android
+
+1. **Edit Markdown file** (in mounted folder)
+2. **Save** - File is immediately on server
+3. **In app: Run Markdown import**
+   - Settings → "Import Markdown Changes"
+   - Or: Auto-import on every sync (future)
+4. **App adopts changes** (if desktop version is newer)
+
+### Conflict Resolution: Last-Write-Wins
+
+**Rule:** Newest version (by `updated` timestamp) wins
+
+**Example:**
+```
+App version:     updated: 2026-01-05 14:00
+Desktop version: updated: 2026-01-05 14:30
+→ Desktop wins (newer timestamp)
+```
+
+**Automatic:**
+- ✅ On Markdown import
+- ✅ On JSON sync
+- ⚠️ No merge conflicts - only complete overwrite
+
+---
+
+## ⚙️ Settings
+
+### Desktop Integration Toggle
+
+**Settings → Desktop Integration**
+
+**ON (activated):**
+- ✅ New notes → automatically exported as `.md`
+- ✅ Updated notes → `.md` update
+- ✅ Deleted notes → `.md` remains (future: also delete)
+
+**OFF (deactivated):**
+- ❌ No Markdown export
+- ✅ JSON sync continues normally
+- ✅ Existing `.md` files remain
+
+### Initial Export
+
+**What happens on activation:**
+1. All existing notes are scanned
+2. Progress dialog shows progress (e.g., "23/42")
+3. Each note is exported as `.md`
+4. On errors: Individual note is skipped
+5. Success message with number of exported notes
+
+**Time:** ~1-2 seconds per 50 notes
+
+---
+
+## 🛠️ Advanced Usage
+
+### Manual Markdown Creation
+
+You can create `.md` files manually:
+
+```markdown
+---
+id: 00000000-0000-0000-0000-000000000001
+created: 2026-01-05T12:00:00Z
+updated: 2026-01-05T12:00:00Z
+---
+
+# New Desktop Note
+
+Content here...
+```
+
+**⚠️ Important:**
+- `id` must be valid UUID (e.g., with uuidgen.io)
+- Timestamps in ISO8601 format
+- Frontmatter enclosed with `---`
+
+### Bulk Operations
+
+**Edit multiple notes at once:**
+
+1. Mount WebDAV
+2. Open all `.md` files in VS Code
+3. Find & Replace across all files (Ctrl+Shift+H)
+4. Save
+5. In app: "Import Markdown Changes"
+
+### Scripting
+
+**Example: Sort all notes by date**
+
+```bash
+#!/bin/bash
+cd /mnt/notes-md/
+
+# Sort all .md files by update date
+for file in *.md; do
+  updated=$(grep "^updated:" "$file" | cut -d' ' -f2)
+  echo "$updated $file"
+done | sort
+```
+
+---
+
+## ❌ Troubleshooting
+
+### "404 Not Found" when mounting WebDAV
+
+**Cause:** `/notes-md/` folder doesn't exist
+
+**Solution:**
+1. **Perform first sync** - Folder is created automatically
+2. OR: Create manually via terminal:
+   ```bash
+   curl -X MKCOL -u noteuser:password http://server:8080/notes-md/
+   ```
+
+### Markdown files don't appear
+
+**Cause:** Desktop integration not activated
+
+**Solution:**
+1. Settings → "Desktop Integration" ON
+2. Wait for initial export
+3. Refresh WebDAV folder
+
+### Changes from desktop don't appear in app
+
+**Cause:** Markdown import not executed
+
+**Solution:**
+1. Settings → "Import Markdown Changes"
+2. OR: Wait for auto-sync (future feature)
+
+### "Frontmatter missing" error
+
+**Cause:** `.md` file without valid YAML frontmatter
+
+**Solution:**
+1. Open file in editor
+2. Add frontmatter at the beginning:
+   ```yaml
+   ---
+   id: NEW-UUID-HERE
+   created: 2026-01-05T12:00:00Z
+   updated: 2026-01-05T12:00:00Z
+   ---
+   ```
+3. Save and import again
+
+---
+
+## 🔒 Security & Best Practices
+
+### Do's ✅
+
+- ✅ **Backup before bulk edits** - Create local backup
+- ✅ **One editor at a time** - Don't edit in app AND desktop in parallel
+- ✅ **Wait for sync** - Run sync before desktop editing
+- ✅ **Respect frontmatter** - Don't change manually (unless you know what you're doing)
+
+### Don'ts ❌
+
+- ❌ **Parallel editing** - App and desktop simultaneously → conflicts
+- ❌ **Delete frontmatter** - Note can't be imported anymore
+- ❌ **Change IDs** - Note is recognized as new
+- ❌ **Manipulate timestamps** - Conflict resolution doesn't work
+
+### Recommended Workflow
+
+```
+1. Sync in app (pull-to-refresh)
+2. Open desktop
+3. Make changes
+4. Save
+5. In app: "Import Markdown Changes"
+6. Verify
+7. Run another sync
+```
+
+---
+
+## 📊 Comparison: JSON vs Markdown
+
+| Aspect | JSON | Markdown |
+|--------|------|----------|
+| **Format** | Structured | Flowing text |
+| **Readability (human)** | ⚠️ Medium | ✅ Good |
+| **Readability (machine)** | ✅ Perfect | ⚠️ Parsing needed |
+| **Metadata** | Native | Frontmatter |
+| **Editors** | Code editors | All text editors |
+| **Sync speed** | ✅ Fast | ⚠️ Slower |
+| **Reliability** | ✅ 100% | ⚠️ Frontmatter errors possible |
+| **Mobile-first** | ✅ Yes | ❌ No |
+| **Desktop-first** | ❌ No | ✅ Yes |
+
+**Conclusion:** Using both formats = Best experience on both platforms!
+
+---
+
+## 🔮 Future Features
+
+Planned for v1.3.0+:
+
+- ⏳ **Auto-Markdown-import** - Automatically on every sync
+- ⏳ **Bidirectional sync** - Without manual import
+- ⏳ **Markdown preview** - In the app
+- ⏳ **Conflict UI** - On simultaneous changes
+- ⏳ **Tags in frontmatter** - Synchronized with app
+- ⏳ **Attachments** - Images/files in Markdown
+
+---
+
+**📚 See also:**
+- [QUICKSTART.en.md](../QUICKSTART.en.md) - App setup
+- [FEATURES.en.md](FEATURES.en.md) - Complete feature list
+- [BACKUP.en.md](BACKUP.en.md) - Backup & restore
+
+**Last update:** v1.2.1 (2026-01-05)

docs/DESKTOP.md

@@ -0,0 +1,505 @@
+# Desktop-Integration 🖥️
+
+**🌍 Languages:** **Deutsch** · [English](DESKTOP.en.md)
+
+> Bearbeite deine Notizen mit jedem Markdown-Editor auf dem Desktop
+
+---
+
+## 📋 Übersicht
+
+Die Desktop-Integration ermöglicht dir, Notizen auf dem PC/Mac zu bearbeiten:
+- 📝 Jeder Markdown-Editor funktioniert
+- 🔄 Automatische Synchronisation über WebDAV
+- 💾 Dual-Format: JSON (Master) + Markdown (Mirror)
+- ⚡ Last-Write-Wins Konfliktauflösung
+
+---
+
+## 🎯 Warum Markdown?
+
+### Dual-Format Architektur
+
+```
+┌─────────────────────────────────────┐
+│         Android App                 │
+│                                     │
+│  ┌──────────┐      ┌─────────────┐ │
+│  │   JSON   │ ──→  │  Markdown   │ │
+│  │ (Master) │      │  (Mirror)   │ │
+│  └──────────┘      └─────────────┘ │
+└────────┬────────────────┬───────────┘
+         │                │
+         ↓                ↓
+    WebDAV Server
+         │                │
+    ┌────┴────┐      ┌────┴──────┐
+    │ /notes/ │      │ /notes-md/│
+    │ *.json  │      │ *.md      │
+    └─────────┘      └───────────┘
+         ↑                ↑
+         │                │
+    ┌────┴────────────────┴───────────┐
+    │      Desktop Editor              │
+    │  (VS Code, Typora, etc.)         │
+    └──────────────────────────────────┘
+```
+
+### Vorteile
+
+**JSON (Master):**
+- ✅ Zuverlässig und schnell
+- ✅ Strukturierte Daten (IDs, Timestamps)
+- ✅ Primärer Sync-Mechanismus
+- ✅ Immer aktiv
+
+**Markdown (Mirror):**
+- ✅ Menschenlesbar
+- ✅ Desktop-Editor kompatibel
+- ✅ Syntax-Highlighting
+- ✅ Optional aktivierbar
+
+---
+
+## 🚀 Schnellstart
+
+### 1. Erste Synchronisation
+
+**Wichtig:** Führe ZUERST einen Sync durch, bevor du Desktop-Integration aktivierst!
+
+1. **App einrichten** (siehe [QUICKSTART.md](QUICKSTART.md))
+2. **Server-Verbindung testen**
+3. **Erste Notiz erstellen**
+4. **Synchronisieren** (Pull-to-Refresh oder Auto-Sync)
+5. ✅ Server erstellt automatisch `/notes/` und `/notes-md/` Ordner
+
+### 2. Desktop-Integration aktivieren
+
+1. **Einstellungen** → **Desktop-Integration**
+2. **Toggle aktivieren**
+3. **Initial Export startet** - Zeigt Progress (X/Y)
+4. ✅ Alle bestehenden Notizen werden als `.md` exportiert
+
+### 3. WebDAV als Netzlaufwerk mounten
+
+#### Windows
+
+```
+1. Explorer öffnen
+2. Rechtsklick auf "Dieser PC"
+3. "Netzlaufwerk verbinden"
+4. URL eingeben: http://DEIN-SERVER:8080/notes-md/
+5. Benutzername: noteuser
+6. Passwort: (dein WebDAV-Passwort)
+7. Laufwerksbuchstabe: Z:\ (oder beliebig)
+8. Fertig!
+```
+
+**Zugriff:** `Z:\` im Explorer
+
+#### macOS
+
+```
+1. Finder öffnen
+2. Menü "Gehe zu" → "Mit Server verbinden" (⌘K)
+3. Server-Adresse: http://DEIN-SERVER:8080/notes-md/
+4. Verbinden
+5. Benutzername: noteuser
+6. Passwort: (dein WebDAV-Passwort)
+7. Fertig!
+```
+
+**Zugriff:** Finder → Netzwerk → notes-md
+
+#### Linux (GNOME)
+
+```
+1. Files / Nautilus öffnen
+2. "Andere Orte"
+3. "Mit Server verbinden"
+4. Server-Adresse: dav://DEIN-SERVER:8080/notes-md/
+5. Benutzername: noteuser
+6. Passwort: (dein WebDAV-Passwort)
+7. Fertig!
+```
+
+**Zugriff:** `/run/user/1000/gvfs/dav:host=...`
+
+#### Linux (davfs2 - permanent)
+
+```bash
+# Installation
+sudo apt install davfs2
+
+# Mount-Point erstellen
+sudo mkdir -p /mnt/notes-md
+
+# Einmalig mounten
+sudo mount -t davfs http://DEIN-SERVER:8080/notes-md/ /mnt/notes-md
+
+# Permanent in /etc/fstab
+echo "http://DEIN-SERVER:8080/notes-md/ /mnt/notes-md davfs rw,user,noauto 0 0" | sudo tee -a /etc/fstab
+```
+
+**Zugriff:** `/mnt/notes-md/`
+
+---
+
+## 📝 Markdown-Editoren
+
+### Empfohlene Editoren
+
+#### 1. VS Code ⭐ _Empfohlen_
+
+**Vorteile:**
+- ✅ Kostenlos & Open Source
+- ✅ Markdown-Preview (Ctrl+Shift+V)
+- ✅ Syntax-Highlighting
+- ✅ Git-Integration
+- ✅ Erweiterungen (Spell Check, etc.)
+
+**Setup:**
+```
+1. VS Code installieren
+2. WebDAV-Laufwerk mounten
+3. Ordner öffnen: Z:\notes-md\ (Windows) oder /mnt/notes-md (Linux)
+4. Fertig! Markdown-Dateien bearbeiten
+```
+
+**Extensions (optional):**
+- `Markdown All in One` - Shortcuts & Preview
+- `Markdown Preview Enhanced` - Bessere Preview
+- `Code Spell Checker` - Rechtschreibprüfung
+
+#### 2. Typora
+
+**Vorteile:**
+- ✅ WYSIWYG Markdown-Editor
+- ✅ Minimalistisches Design
+- ✅ Live-Preview
+- ⚠️ Kostenpflichtig (~15€)
+
+**Setup:**
+```
+1. Typora installieren
+2. WebDAV mounten
+3. Ordner in Typora öffnen
+4. Notizen bearbeiten
+```
+
+#### 3. Notepad++
+
+**Vorteile:**
+- ✅ Leichtgewichtig
+- ✅ Schnell
+- ✅ Syntax-Highlighting
+- ⚠️ Keine Markdown-Preview
+
+**Setup:**
+```
+1. Notepad++ installieren
+2. WebDAV mounten
+3. Dateien direkt öffnen
+```
+
+#### 4. Obsidian
+
+**Vorteile:**
+- ✅ Zweite Gehirn-Philosophie
+- ✅ Graph-View für Verlinkungen
+- ✅ Viele Plugins
+- ⚠️ Sync-Konflikte möglich (2 Master)
+
+**Setup:**
+```
+1. Obsidian installieren
+2. WebDAV als Vault öffnen
+3. Vorsicht: Obsidian erstellt eigene Metadaten!
+```
+
+**⚠️ Nicht empfohlen:** Kann Frontmatter verändern
+
+---
+
+## 📄 Markdown-Dateiformat
+
+### Struktur
+
+Jede Notiz wird als `.md` Datei mit YAML-Frontmatter exportiert:
+
+```markdown
+---
+id: abc-123-def-456
+created: 2026-01-05T14:30:22Z
+updated: 2026-01-05T14:30:22Z
+tags: []
+---
+
+# Notiz-Titel
+
+Notiz-Inhalt hier...
+```
+
+### Frontmatter-Felder
+
+| Feld | Typ | Beschreibung | Pflicht |
+|------|-----|--------------|---------|
+| `id` | UUID | Eindeutige Notiz-ID | ✅ Ja |
+| `created` | ISO8601 | Erstellungsdatum | ✅ Ja |
+| `updated` | ISO8601 | Änderungsdatum | ✅ Ja |
+| `tags` | Array | Tags (zukünftig) | ❌ Nein |
+
+### Dateinamen
+
+**Sanitization-Regeln:**
+```
+Titel: "Meine Einkaufsliste 🛒"
+→ Dateiname: "Meine_Einkaufsliste.md"
+
+Entfernt werden:
+- Emojis: 🛒 → entfernt
+- Sonderzeichen: / \ : * ? " < > | → entfernt
+- Mehrfache Leerzeichen → einzelnes Leerzeichen
+- Leerzeichen → Unterstrich _
+```
+
+**Beispiele:**
+```
+"Meeting Notes 2026" → "Meeting_Notes_2026.md"
+"To-Do: Projekt" → "To-Do_Projekt.md"
+"Urlaub ☀️" → "Urlaub.md"
+```
+
+---
+
+## 🔄 Synchronisation
+
+### Workflow: Android → Desktop
+
+1. **Notiz in App erstellen/bearbeiten**
+2. **Sync ausführen** (Auto oder manuell)
+3. **JSON wird hochgeladen** (`/notes/abc-123.json`)
+4. **Markdown wird exportiert** (`/notes-md/Notiz_Titel.md`) _(nur wenn Desktop-Integration AN)_
+5. **Desktop-Editor zeigt Änderungen** (nach Refresh)
+
+### Workflow: Desktop → Android
+
+1. **Markdown-Datei bearbeiten** (im gemounteten Ordner)
+2. **Speichern** - Datei liegt sofort auf Server
+3. **In App: Markdown-Import ausführen**
+   - Einstellungen → "Import Markdown Changes"
+   - Oder: Auto-Import bei jedem Sync (zukünftig)
+4. **App übernimmt Änderungen** (wenn Desktop-Version neuer)
+
+### Konfliktauflösung: Last-Write-Wins
+
+**Regel:** Neueste Version (nach `updated` Timestamp) gewinnt
+
+**Beispiel:**
+```
+App-Version:     updated: 2026-01-05 14:00
+Desktop-Version: updated: 2026-01-05 14:30
+→ Desktop gewinnt (neuerer Timestamp)
+```
+
+**Automatisch:**
+- ✅ Beim Markdown-Import
+- ✅ Beim JSON-Sync
+- ⚠️ Keine Merge-Konflikte - nur komplettes Überschreiben
+
+---
+
+## ⚙️ Einstellungen
+
+### Desktop-Integration Toggle
+
+**Einstellungen → Desktop-Integration**
+
+**AN (aktiviert):**
+- ✅ Neue Notizen → automatisch als `.md` exportiert
+- ✅ Aktualisierte Notizen → `.md` Update
+- ✅ Gelöschte Notizen → `.md` bleibt (zukünftig: auch löschen)
+
+**AUS (deaktiviert):**
+- ❌ Kein Markdown-Export
+- ✅ JSON-Sync läuft normal weiter
+- ✅ Bestehende `.md` Dateien bleiben erhalten
+
+### Initial Export
+
+**Was passiert beim Aktivieren:**
+1. Alle bestehenden Notizen werden gescannt
+2. Progress-Dialog zeigt Fortschritt (z.B. "23/42")
+3. Jede Notiz wird als `.md` exportiert
+4. Bei Fehlern: Einzelne Notiz wird übersprungen
+5. Erfolgsmeldung mit Anzahl exportierter Notizen
+
+**Zeit:** ~1-2 Sekunden pro 50 Notizen
+
+---
+
+## 🛠️ Erweiterte Nutzung
+
+### Manuelle Markdown-Erstellung
+
+Du kannst `.md` Dateien manuell erstellen:
+
+```markdown
+---
+id: 00000000-0000-0000-0000-000000000001
+created: 2026-01-05T12:00:00Z
+updated: 2026-01-05T12:00:00Z
+---
+
+# Neue Desktop-Notiz
+
+Inhalt hier...
+```
+
+**⚠️ Wichtig:**
+- `id` muss gültige UUID sein (z.B. mit uuidgen.io)
+- Timestamps in ISO8601-Format
+- Frontmatter mit `---` umschließen
+
+### Bulk-Operations
+
+**Mehrere Notizen auf einmal bearbeiten:**
+
+1. WebDAV mounten
+2. Alle `.md` Dateien in VS Code öffnen
+3. Suchen & Ersetzen über alle Dateien (Ctrl+Shift+H)
+4. Speichern
+5. In App: "Import Markdown Changes"
+
+### Scripting
+
+**Beispiel: Alle Notizen nach Datum sortieren**
+
+```bash
+#!/bin/bash
+cd /mnt/notes-md/
+
+# Alle .md Dateien nach Update-Datum sortieren
+for file in *.md; do
+  updated=$(grep "^updated:" "$file" | cut -d' ' -f2)
+  echo "$updated $file"
+done | sort
+```
+
+---
+
+## ❌ Fehlerbehebung
+
+### "404 Not Found" beim WebDAV-Mount
+
+**Ursache:** `/notes-md/` Ordner existiert nicht
+
+**Lösung:**
+1. **Erste Sync durchführen** - Ordner wird automatisch erstellt
+2. ODER: Manuell erstellen via Terminal:
+   ```bash
+   curl -X MKCOL -u noteuser:password http://server:8080/notes-md/
+   ```
+
+### Markdown-Dateien erscheinen nicht
+
+**Ursache:** Desktop-Integration nicht aktiviert
+
+**Lösung:**
+1. Einstellungen → "Desktop-Integration" AN
+2. Warten auf Initial Export
+3. WebDAV-Ordner refreshen
+
+### Änderungen vom Desktop erscheinen nicht in App
+
+**Ursache:** Markdown-Import nicht ausgeführt
+
+**Lösung:**
+1. Einstellungen → "Import Markdown Changes"
+2. ODER: Auto-Sync abwarten (zukünftiges Feature)
+
+### "Frontmatter fehlt" Fehler
+
+**Ursache:** `.md` Datei ohne gültiges YAML-Frontmatter
+
+**Lösung:**
+1. Datei in Editor öffnen
+2. Frontmatter am Anfang hinzufügen:
+   ```yaml
+   ---
+   id: NEUE-UUID-HIER
+   created: 2026-01-05T12:00:00Z
+   updated: 2026-01-05T12:00:00Z
+   ---
+   ```
+3. Speichern und erneut importieren
+
+---
+
+## 🔒 Sicherheit & Best Practices
+
+### Do's ✅
+
+- ✅ **Backup vor Bulk-Edits** - Lokales Backup erstellen
+- ✅ **Ein Editor zur Zeit** - Nicht parallel in App UND Desktop bearbeiten
+- ✅ **Sync abwarten** - Vor Desktop-Bearbeitung Sync durchführen
+- ✅ **Frontmatter respektieren** - Nicht manuell ändern (außer du weißt was du tust)
+
+### Don'ts ❌
+
+- ❌ **Parallel bearbeiten** - App und Desktop gleichzeitig → Konflikte
+- ❌ **Frontmatter löschen** - Notiz kann nicht mehr importiert werden
+- ❌ **IDs ändern** - Notiz wird als neue erkannt
+- ❌ **Timestamps manipulieren** - Konfliktauflösung funktioniert nicht
+
+### Empfohlener Workflow
+
+```
+1. Sync in App (Pull-to-Refresh)
+2. Desktop öffnen
+3. Änderungen machen
+4. Speichern
+5. In App: "Import Markdown Changes"
+6. Überprüfen
+7. Weiteren Sync durchführen
+```
+
+---
+
+## 📊 Vergleich: JSON vs Markdown
+
+| Aspekt | JSON | Markdown |
+|--------|------|----------|
+| **Format** | Strukturiert | Fließtext |
+| **Lesbarkeit (Mensch)** | ⚠️ Mittel | ✅ Gut |
+| **Lesbarkeit (Maschine)** | ✅ Perfekt | ⚠️ Parsing nötig |
+| **Metadata** | Native | Frontmatter |
+| **Editoren** | Code-Editoren | Alle Text-Editoren |
+| **Sync-Geschwindigkeit** | ✅ Schnell | ⚠️ Langsamer |
+| **Zuverlässigkeit** | ✅ 100% | ⚠️ Frontmatter-Fehler möglich |
+| **Mobile-First** | ✅ Ja | ❌ Nein |
+| **Desktop-First** | ❌ Nein | ✅ Ja |
+
+**Fazit:** Beide Formate nutzen = Beste Erfahrung auf beiden Plattformen!
+
+---
+
+## 🔮 Zukünftige Features
+
+Geplant für v1.3.0+:
+
+- ⏳ **Auto-Markdown-Import** - Bei jedem Sync automatisch
+- ⏳ **Bidirektionaler Sync** - Ohne manuellen Import
+- ⏳ **Markdown-Vorschau** - In der App
+- ⏳ **Konflikts-UI** - Bei gleichzeitigen Änderungen
+- ⏳ **Tags in Frontmatter** - Synchronisiert mit App
+- ⏳ **Attachments** - Bilder/Dateien in Markdown
+
+---
+
+**📚 Siehe auch:**
+- [QUICKSTART.md](../QUICKSTART.md) - App-Einrichtung
+- [FEATURES.md](FEATURES.md) - Vollständige Feature-Liste
+- [BACKUP.md](BACKUP.md) - Backup & Wiederherstellung
+
+**Letzte Aktualisierung:** v1.2.1 (2026-01-05)

docs/DOCS.en.md

@@ -0,0 +1,529 @@
+# Simple Notes Sync - Technical Documentation
+
+This file contains detailed technical information about implementation, architecture, and advanced features.
+
+**🌍 Languages:** [Deutsch](DOCS.md) · **English**
+
+---
+
+## 📐 Architecture
+
+### Overall Overview
+
+```
+┌─────────────────┐
+│  Android App    │
+│  (Kotlin)       │
+└────────┬────────┘
+         │ WebDAV/HTTP
+         │
+┌────────▼────────┐
+│  WebDAV Server  │
+│  (Docker)       │
+└─────────────────┘
+```
+
+### Android App Architecture
+
+```
+app/
+├── models/
+│   ├── Note.kt              # Data class for notes
+│   └── SyncStatus.kt        # Sync status enum
+├── storage/
+│   └── NotesStorage.kt      # Local JSON file storage
+├── sync/
+│   ├── WebDavSyncService.kt # WebDAV sync logic
+│   ├── NetworkMonitor.kt    # WiFi detection
+│   ├── SyncWorker.kt        # WorkManager background worker
+│   └── BootReceiver.kt      # Device reboot handler
+├── adapters/
+│   └── NotesAdapter.kt      # RecyclerView adapter
+├── utils/
+│   ├── Constants.kt         # App constants
+│   ├── NotificationHelper.kt# Notification management
+│   └── Logger.kt            # Debug/release logging
+└── activities/
+    ├── MainActivity.kt      # Main view with list
+    ├── NoteEditorActivity.kt# Note editor
+    └── SettingsActivity.kt  # Server configuration
+```
+
+---
+
+## 🔄 Auto-Sync Implementation
+
+### WorkManager Periodic Task
+
+Auto-sync is based on **WorkManager** with the following configuration:
+
+```kotlin
+val constraints = Constraints.Builder()
+    .setRequiredNetworkType(NetworkType.UNMETERED)  // WiFi only
+    .build()
+
+val syncRequest = PeriodicWorkRequestBuilder<SyncWorker>(
+    30, TimeUnit.MINUTES,  // Every 30 minutes
+    10, TimeUnit.MINUTES   // Flex interval
+)
+    .setConstraints(constraints)
+    .build()
+```
+
+**Why WorkManager?**
+- ✅ Runs even when app is closed
+- ✅ Automatic restart after device reboot
+- ✅ Battery-efficient (Android managed)
+- ✅ Guaranteed execution when constraints are met
+
+### Network Detection
+
+Instead of SSID-based detection (Android 13+ privacy issues), we use **Gateway IP Comparison**:
+
+```kotlin
+fun isInHomeNetwork(): Boolean {
+    val gatewayIP = getGatewayIP()         // e.g. 192.168.0.1
+    val serverIP = extractIPFromUrl(serverUrl)  // e.g. 192.168.0.188
+    
+    return isSameNetwork(gatewayIP, serverIP)  // Checks /24 network
+}
+```
+
+**Advantages:**
+- ✅ No location permissions needed
+- ✅ Works with all Android versions
+- ✅ Reliable and fast
+
+### Sync Flow
+
+```
+1. WorkManager wakes up (every 30 min)
+   ↓
+2. Check: WiFi connected?
+   ↓
+3. Check: Same network as server?
+   ↓
+4. Load local notes
+   ↓
+5. Upload new/changed notes → Server
+   ↓
+6. Download remote notes ← Server
+   ↓
+7. Merge & resolve conflicts
+   ↓
+8. Update local storage
+   ↓
+9. Show notification (if changes)
+```
+
+---
+
+## <20> Sync Trigger Overview
+
+The app uses **4 different sync triggers** with different use cases:
+
+| Trigger | File | Function | When? | Pre-Check? |
+|---------|------|----------|-------|------------|
+| **1. Manual Sync** | `MainActivity.kt` | `triggerManualSync()` | User clicks sync button in menu | ✅ Yes |
+| **2. Auto-Sync (onResume)** | `MainActivity.kt` | `triggerAutoSync()` | App opened/resumed | ✅ Yes |
+| **3. Background Sync (Periodic)** | `SyncWorker.kt` | `doWork()` | Every 15/30/60 minutes (configurable) | ✅ Yes |
+| **4. WiFi-Connect Sync** | `NetworkMonitor.kt` → `SyncWorker.kt` | `triggerWifiConnectSync()` | WiFi enabled/SSID changed | ✅ Yes |
+
+### Server Reachability Check (Pre-Check)
+
+**All 4 sync triggers** use a **pre-check** before the actual sync:
+
+```kotlin
+// WebDavSyncService.kt - isServerReachable()
+suspend fun isServerReachable(): Boolean = withContext(Dispatchers.IO) {
+    return@withContext try {
+        Socket().use { socket ->
+            socket.connect(InetSocketAddress(host, port), 2000)  // 2s Timeout
+        }
+        true
+    } catch (e: Exception) {
+        Logger.d(TAG, "Server not reachable: ${e.message}")
+        false
+    }
+}
+```
+
+**Why Socket Check instead of HTTP Request?**
+- ⚡ **Faster:** Socket connect is instant, HTTP request takes longer
+- 🔋 **Battery Efficient:** No HTTP overhead (headers, TLS handshake, etc.)
+- 🎯 **More Precise:** Only checks network reachability, not server logic
+- 🛡️ **Prevents Errors:** Detects foreign WiFi networks before sync error occurs
+
+**When does the check fail?**
+- ❌ Server offline/unreachable
+- ❌ Wrong WiFi network (e.g. public café WiFi)
+- ❌ Network not ready yet (DHCP/routing delay after WiFi connect)
+- ❌ VPN blocks server access
+- ❌ No WebDAV server URL configured
+
+### Sync Behavior by Trigger Type
+
+| Trigger | When server not reachable | On successful sync | Throttling |
+|---------|--------------------------|-------------------|------------|
+| Manual Sync | Toast: "Server not reachable" | Toast: "✅ Synced: X notes" | None |
+| Auto-Sync (onResume) | Silent abort (no toast) | Toast: "✅ Synced: X notes" | Max. 1x/min |
+| Background Sync | Silent abort (no toast) | Silent (LocalBroadcast only) | 15/30/60 min |
+| WiFi-Connect Sync | Silent abort (no toast) | Silent (LocalBroadcast only) | SSID-based |
+
+---
+
+## <20>🔋 Battery Optimization
+
+### Usage Analysis
+
+| Component | Frequency | Usage | Details |
+|------------|----------|-----------|---------|
+| WorkManager Wakeup | Every 30 min | ~0.15 mAh | System wakes up |
+| Network Check | 48x/day | ~0.03 mAh | Gateway IP check |
+| WebDAV Sync | 2-3x/day | ~1.5 mAh | Only when changes |
+| **Total** | - | **~12 mAh/day** | **~0.4%** at 3000mAh |
+
+### Optimizations
+
+1. **IP Caching**
+   ```kotlin
+   private var cachedServerIP: String? = null
+   // DNS lookup only once at start, not every check
+   ```
+
+2. **Throttling**
+   ```kotlin
+   private var lastSyncTime = 0L
+   private const val MIN_SYNC_INTERVAL_MS = 60_000L  // Max 1 sync/min
+   ```
+
+3. **Conditional Logging**
+   ```kotlin
+   object Logger {
+       fun d(tag: String, msg: String) {
+           if (BuildConfig.DEBUG) Log.d(tag, msg)
+       }
+   }
+   ```
+
+4. **Network Constraints**
+   - WiFi only (not mobile data)
+   - Only when server is reachable
+   - No permanent listeners
+
+---
+
+## 📦 WebDAV Sync Details
+
+### Upload Flow
+
+```kotlin
+suspend fun uploadNotes(): Int {
+    val localNotes = storage.loadAllNotes()
+    var uploadedCount = 0
+    
+    for (note in localNotes) {
+        if (note.syncStatus == SyncStatus.PENDING) {
+            val jsonContent = note.toJson()
+            val remotePath = "$serverUrl/${note.id}.json"
+            
+            sardine.put(remotePath, jsonContent.toByteArray())
+            
+            note.syncStatus = SyncStatus.SYNCED
+            storage.saveNote(note)
+            uploadedCount++
+        }
+    }
+    
+    return uploadedCount
+}
+```
+
+### Download Flow
+
+```kotlin
+suspend fun downloadNotes(): DownloadResult {
+    val remoteFiles = sardine.list(serverUrl)
+    var downloadedCount = 0
+    var conflictCount = 0
+    
+    for (file in remoteFiles) {
+        if (!file.name.endsWith(".json")) continue
+        
+        val content = sardine.get(file.href)
+        val remoteNote = Note.fromJson(content)
+        val localNote = storage.loadNote(remoteNote.id)
+        
+        if (localNote == null) {
+            // New note from server
+            storage.saveNote(remoteNote)
+            downloadedCount++
+        } else if (localNote.modifiedAt < remoteNote.modifiedAt) {
+            // Server has newer version
+            storage.saveNote(remoteNote)
+            downloadedCount++
+        } else if (localNote.modifiedAt > remoteNote.modifiedAt) {
+            // Local version is newer → Conflict
+            resolveConflict(localNote, remoteNote)
+            conflictCount++
+        }
+    }
+    
+    return DownloadResult(downloadedCount, conflictCount)
+}
+```
+
+### Conflict Resolution
+
+Strategy: **Last-Write-Wins** with **Conflict Copy**
+
+```kotlin
+fun resolveConflict(local: Note, remote: Note) {
+    // Rename remote note (conflict copy)
+    val conflictNote = remote.copy(
+        id = "${remote.id}_conflict_${System.currentTimeMillis()}",
+        title = "${remote.title} (Conflict)"
+    )
+    
+    storage.saveNote(conflictNote)
+    
+    // Local note remains
+    local.syncStatus = SyncStatus.SYNCED
+    storage.saveNote(local)
+}
+```
+
+---
+
+## 🔔 Notifications
+
+### Notification Channels
+
+```kotlin
+val channel = NotificationChannel(
+    "notes_sync_channel",
+    "Notes Synchronization",
+    NotificationManager.IMPORTANCE_DEFAULT
+)
+```
+
+### Success Notification
+
+```kotlin
+fun showSyncSuccess(context: Context, count: Int) {
+    val intent = Intent(context, MainActivity::class.java)
+    val pendingIntent = PendingIntent.getActivity(context, 0, intent, FLAGS)
+    
+    val notification = NotificationCompat.Builder(context, CHANNEL_ID)
+        .setContentTitle("Sync successful")
+        .setContentText("$count notes synchronized")
+        .setContentIntent(pendingIntent)  // Click opens app
+        .setAutoCancel(true)              // Dismiss on click
+        .build()
+    
+    notificationManager.notify(NOTIFICATION_ID, notification)
+}
+```
+
+---
+
+## 🛡️ Permissions
+
+The app requires **minimal permissions**:
+
+```xml
+<!-- Network -->
+<uses-permission android:name="android.permission.INTERNET" />
+<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
+<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
+
+<!-- Notifications -->
+<uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
+
+<!-- Boot Receiver -->
+<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
+
+<!-- Battery Optimization (optional) -->
+<uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />
+```
+
+**No Location Permissions!**  
+Earlier versions required `ACCESS_FINE_LOCATION` for SSID detection. Now we use Gateway IP Comparison.
+
+---
+
+## 🧪 Testing
+
+### Test Server
+
+```bash
+# WebDAV server reachable?
+curl -u noteuser:password http://192.168.0.188:8080/
+
+# Upload file
+echo '{"test":"data"}' > test.json
+curl -u noteuser:password -T test.json http://192.168.0.188:8080/test.json
+
+# Download file
+curl -u noteuser:password http://192.168.0.188:8080/test.json
+```
+
+### Test Android App
+
+**Unit Tests:**
+```bash
+cd android
+./gradlew test
+```
+
+**Instrumented Tests:**
+```bash
+./gradlew connectedAndroidTest
+```
+
+**Manual Testing Checklist:**
+
+- [ ] Create note → visible in list
+- [ ] Edit note → changes saved
+- [ ] Delete note → removed from list
+- [ ] Manual sync → server status "Reachable"
+- [ ] Auto-sync → notification after ~30 min
+- [ ] Close app → auto-sync continues
+- [ ] Device reboot → auto-sync starts automatically
+- [ ] Server offline → error notification
+- [ ] Notification click → app opens
+
+---
+
+## 🚀 Build & Deployment
+
+### Debug Build
+
+```bash
+cd android
+./gradlew assembleDebug
+# APK: app/build/outputs/apk/debug/app-debug.apk
+```
+
+### Release Build
+
+```bash
+./gradlew assembleRelease
+# APK: app/build/outputs/apk/release/app-release-unsigned.apk
+```
+
+### Sign (for Distribution)
+
+```bash
+# Create keystore
+keytool -genkey -v -keystore my-release-key.jks -keyalg RSA -keysize 2048 -validity 10000 -alias my-alias
+
+# Sign APK
+jarsigner -verbose -sigalg SHA256withRSA -digestalg SHA-256 \
+  -keystore my-release-key.jks \
+  app-release-unsigned.apk my-alias
+
+# Optimize
+zipalign -v 4 app-release-unsigned.apk app-release.apk
+```
+
+---
+
+## 🐛 Debugging
+
+### LogCat Filter
+
+```bash
+# Only app logs
+adb logcat -s SimpleNotesApp NetworkMonitor SyncWorker WebDavSyncService
+
+# With timestamps
+adb logcat -v time -s SyncWorker
+
+# Save to file
+adb logcat -s SyncWorker > sync_debug.log
+```
+
+### Common Issues
+
+**Problem: Auto-sync not working**
+```
+Solution: Disable battery optimization
+Settings → Apps → Simple Notes → Battery → Don't optimize
+```
+
+**Problem: Server not reachable**
+```
+Check: 
+1. Server running? → docker-compose ps
+2. IP correct? → ip addr show
+3. Port open? → telnet 192.168.0.188 8080
+4. Firewall? → sudo ufw allow 8080
+```
+
+**Problem: Notifications not appearing**
+```
+Check:
+1. Notification permission granted?
+2. Do Not Disturb active?
+3. App in background? → Force stop & restart
+```
+
+---
+
+## 📚 Dependencies
+
+```gradle
+// Core
+androidx.core:core-ktx:1.12.0
+androidx.appcompat:appcompat:1.6.1
+com.google.android.material:material:1.11.0
+
+// Lifecycle
+androidx.lifecycle:lifecycle-runtime-ktx:2.7.0
+
+// RecyclerView
+androidx.recyclerview:recyclerview:1.3.2
+
+// Coroutines
+org.jetbrains.kotlinx:kotlinx-coroutines-android:1.7.3
+
+// WorkManager
+androidx.work:work-runtime-ktx:2.9.0
+
+// WebDAV Client
+com.github.thegrizzlylabs:sardine-android:0.8
+
+// Broadcast (deprecated but working)
+androidx.localbroadcastmanager:localbroadcastmanager:1.1.0
+```
+
+---
+
+## 🔮 Roadmap
+
+### v1.1
+- [ ] Search & Filter
+- [ ] Dark Mode
+- [ ] Tags/Categories
+- [ ] Markdown Preview
+
+### v2.0
+- [ ] Desktop Client (Flutter)
+- [ ] End-to-End Encryption
+- [ ] Shared Notes (Collaboration)
+- [ ] Attachment Support
+
+---
+
+## 📖 Further Documentation
+
+- [Project Docs](https://github.com/inventory69/project-docs/tree/main/simple-notes-sync)
+- [Sync Architecture](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/SYNC_ARCHITECTURE.md) - **Detailed Sync Trigger Documentation**
+- [Android Guide](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/ANDROID_GUIDE.md)
+- [Bugfix Documentation](https://github.com/inventory69/project-docs/blob/main/simple-notes-sync/BUGFIX_SYNC_SPAM_AND_NOTIFICATIONS.md)
+
+---
+
+**Last updated:** December 25, 2025