v1.5.0: Jetpack Compose Settings Redesign + Fixes

Features:
- ✨ Complete Settings UI redesign with Jetpack Compose
- 🎨 Material 3 Design with Dynamic Colors (Material You)
- 📊 6 logical settings groups in separate screens:
  * Server Settings (URL, Credentials, Connection Test)
  * Sync Settings (Auto-Sync, Interval 15/30/60 min)
  * Markdown Desktop Integration (Auto-Sync for .md files)
  * Backup & Restore (Local/Server)
  * About this App (Version, GitHub, License)
  * Debug & Diagnostics (File Logging, Log Export)

Bugfixes (ported from old SettingsActivity):
- 🔧 Fix #1: Server URL prefix (http://|https://) auto-set on init
- 🔧 Fix #2: Battery optimization dialog on Auto-Sync enable
- 🔧 Fix #3: Markdown initial export on feature activation

Implementation Details:
- SettingsViewModel with Kotlin Flows state management
- SettingsEvent system for Activity-level actions (dialogs, intents)
- Reusable Compose components (SettingsCard, Switch, RadioGroup, etc.)
- Progress dialog for markdown initial export
- Edge-to-edge display with system bar handling
- Navigation Compose for screen transitions with back button

Breaking Changes:
- Old SettingsActivity.kt (1147 lines) no longer used
  (Can be removed in future as legacy code)

android/app/src/main/AndroidManifest.xml

@@ -43,11 +43,17 @@
             android:windowSoftInputMode="adjustResize"
             android:parentActivityName=".MainActivity" />
 
-        <!-- Settings Activity -->
+        <!-- Settings Activity (Legacy - XML-based) -->
         <activity
             android:name=".SettingsActivity"
             android:parentActivityName=".MainActivity" />
 
+        <!-- Settings Activity v1.5.0 (Jetpack Compose) -->
+        <activity
+            android:name=".ui.settings.ComposeSettingsActivity"
+            android:parentActivityName=".MainActivity"
+            android:theme="@style/Theme.SimpleNotes" />
+
         <!-- Boot Receiver - Startet WorkManager nach Reboot -->
         <receiver
             android:name=".sync.BootReceiver"

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

@@ -638,7 +638,8 @@ class MainActivity : AppCompatActivity() {
     }
     
     private fun openSettings() {
-        val intent = Intent(this, SettingsActivity::class.java)
+        // v1.5.0: Use new Jetpack Compose Settings
+        val intent = Intent(this, dev.dettmer.simplenotes.ui.settings.ComposeSettingsActivity::class.java)
         @Suppress("DEPRECATION")
         startActivityForResult(intent, REQUEST_SETTINGS)
     }

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/ComposeSettingsActivity.kt

@@ -0,0 +1,208 @@
+package dev.dettmer.simplenotes.ui.settings
+
+import android.content.Context
+import android.content.Intent
+import android.net.Uri
+import android.os.Build
+import android.os.Bundle
+import android.os.PowerManager
+import android.provider.Settings
+import android.widget.Toast
+import androidx.activity.ComponentActivity
+import androidx.activity.compose.setContent
+import androidx.activity.enableEdgeToEdge
+import androidx.activity.viewModels
+import androidx.appcompat.app.AlertDialog
+import androidx.compose.foundation.isSystemInDarkTheme
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.darkColorScheme
+import androidx.compose.material3.dynamicDarkColorScheme
+import androidx.compose.material3.dynamicLightColorScheme
+import androidx.compose.material3.lightColorScheme
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.ui.platform.LocalContext
+import androidx.navigation.compose.rememberNavController
+import com.google.android.material.color.DynamicColors
+import dev.dettmer.simplenotes.SimpleNotesApplication
+import dev.dettmer.simplenotes.utils.Logger
+import androidx.lifecycle.lifecycleScope
+import kotlinx.coroutines.launch
+
+/**
+ * Settings Activity with Jetpack Compose UI
+ * v1.5.0: Complete Settings Redesign with grouped screens
+ * 
+ * Replaces the old 1147-line SettingsActivity.kt with a modern
+ * Compose-based implementation featuring:
+ * - 6 logical settings groups as separate screens
+ * - Material 3 Design with Dynamic Colors (Material You)
+ * - Navigation with back button in each screen
+ * - Clean separation of concerns with SettingsViewModel
+ */
+class ComposeSettingsActivity : ComponentActivity() {
+    
+    companion object {
+        private const val TAG = "ComposeSettingsActivity"
+    }
+    
+    private val viewModel: SettingsViewModel by viewModels()
+    
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        
+        // Apply Dynamic Colors for Material You (Android 12+)
+        DynamicColors.applyToActivityIfAvailable(this)
+        
+        // Enable edge-to-edge display
+        enableEdgeToEdge()
+        
+        // Collect events from ViewModel (for Activity-level actions)
+        collectViewModelEvents()
+        
+        setContent {
+            SimpleNotesSettingsTheme {
+                val navController = rememberNavController()
+                val context = LocalContext.current
+                
+                // Toast handling from ViewModel
+                LaunchedEffect(Unit) {
+                    viewModel.showToast.collect { message ->
+                        Toast.makeText(context, message, Toast.LENGTH_SHORT).show()
+                    }
+                }
+                
+                SettingsNavHost(
+                    navController = navController,
+                    viewModel = viewModel,
+                    onFinish = {
+                        setResult(RESULT_OK)
+                        finish()
+                    }
+                )
+            }
+        }
+    }
+    
+    /**
+     * Collect events from ViewModel for Activity-level actions
+     * v1.5.0: Ported from old SettingsActivity
+     */
+    private fun collectViewModelEvents() {
+        lifecycleScope.launch {
+            viewModel.events.collect { event ->
+                when (event) {
+                    is SettingsViewModel.SettingsEvent.RequestBatteryOptimization -> {
+                        checkBatteryOptimization()
+                    }
+                    is SettingsViewModel.SettingsEvent.RestartNetworkMonitor -> {
+                        restartNetworkMonitor()
+                    }
+                }
+            }
+        }
+    }
+    
+    /**
+     * Check if battery optimization is disabled for this app
+     * v1.5.0: Ported from old SettingsActivity
+     */
+    private fun checkBatteryOptimization() {
+        val powerManager = getSystemService(Context.POWER_SERVICE) as PowerManager
+        
+        if (!powerManager.isIgnoringBatteryOptimizations(packageName)) {
+            showBatteryOptimizationDialog()
+        }
+    }
+    
+    /**
+     * Show dialog asking user to disable battery optimization
+     * v1.5.0: Ported from old SettingsActivity
+     */
+    private fun showBatteryOptimizationDialog() {
+        AlertDialog.Builder(this)
+            .setTitle("Hintergrund-Synchronisation")
+            .setMessage(
+                "Damit die App im Hintergrund synchronisieren kann, " +
+                "muss die Akku-Optimierung deaktiviert werden.\n\n" +
+                "Bitte wähle 'Nicht optimieren' für Simple Notes."
+            )
+            .setPositiveButton("Einstellungen öffnen") { _, _ ->
+                openBatteryOptimizationSettings()
+            }
+            .setNegativeButton("Später") { dialog, _ ->
+                dialog.dismiss()
+            }
+            .setCancelable(false)
+            .show()
+    }
+    
+    /**
+     * Open system battery optimization settings
+     * v1.5.0: Ported from old SettingsActivity
+     */
+    private fun openBatteryOptimizationSettings() {
+        try {
+            val intent = Intent(Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS)
+            intent.data = Uri.parse("package:$packageName")
+            startActivity(intent)
+        } catch (e: Exception) {
+            Logger.w(TAG, "Failed to open battery optimization settings: ${e.message}")
+            // Fallback: Open general battery settings
+            try {
+                val intent = Intent(Settings.ACTION_IGNORE_BATTERY_OPTIMIZATION_SETTINGS)
+                startActivity(intent)
+            } catch (e2: Exception) {
+                Logger.w(TAG, "Failed to open fallback battery settings: ${e2.message}")
+                Toast.makeText(this, "Bitte Akku-Optimierung manuell deaktivieren", Toast.LENGTH_LONG).show()
+            }
+        }
+    }
+    
+    /**
+     * Restart the network monitor after sync settings change
+     * v1.5.0: Ported from old SettingsActivity
+     */
+    private fun restartNetworkMonitor() {
+        try {
+            val app = application as SimpleNotesApplication
+            Logger.d(TAG, "🔄 Restarting NetworkMonitor with new settings")
+            app.networkMonitor.stopMonitoring()
+            app.networkMonitor.startMonitoring()
+            Logger.d(TAG, "✅ NetworkMonitor restarted successfully")
+        } catch (e: Exception) {
+            Logger.e(TAG, "❌ Failed to restart NetworkMonitor: ${e.message}")
+        }
+    }
+}
+
+/**
+ * Material 3 Theme with Dynamic Colors support
+ */
+@Composable
+fun SimpleNotesSettingsTheme(
+    darkTheme: Boolean = isSystemInDarkTheme(),
+    dynamicColor: Boolean = true,
+    content: @Composable () -> Unit
+) {
+    val context = LocalContext.current
+    
+    val colorScheme = when {
+        // Dynamic colors are available on Android 12+
+        dynamicColor && Build.VERSION.SDK_INT >= Build.VERSION_CODES.S -> {
+            if (darkTheme) {
+                dynamicDarkColorScheme(context)
+            } else {
+                dynamicLightColorScheme(context)
+            }
+        }
+        // Fallback to static Material 3 colors
+        darkTheme -> darkColorScheme()
+        else -> lightColorScheme()
+    }
+    
+    MaterialTheme(
+        colorScheme = colorScheme,
+        content = content
+    )
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/SettingsNavigation.kt

@@ -0,0 +1,85 @@
+package dev.dettmer.simplenotes.ui.settings
+
+import androidx.compose.runtime.Composable
+import androidx.navigation.NavHostController
+import androidx.navigation.compose.NavHost
+import androidx.navigation.compose.composable
+import dev.dettmer.simplenotes.ui.settings.screens.AboutScreen
+import dev.dettmer.simplenotes.ui.settings.screens.BackupSettingsScreen
+import dev.dettmer.simplenotes.ui.settings.screens.DebugSettingsScreen
+import dev.dettmer.simplenotes.ui.settings.screens.MarkdownSettingsScreen
+import dev.dettmer.simplenotes.ui.settings.screens.ServerSettingsScreen
+import dev.dettmer.simplenotes.ui.settings.screens.SettingsMainScreen
+import dev.dettmer.simplenotes.ui.settings.screens.SyncSettingsScreen
+
+/**
+ * Settings navigation host with all routes
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun SettingsNavHost(
+    navController: NavHostController,
+    viewModel: SettingsViewModel,
+    onFinish: () -> Unit
+) {
+    NavHost(
+        navController = navController,
+        startDestination = SettingsRoute.Main.route
+    ) {
+        // Main Settings Overview
+        composable(SettingsRoute.Main.route) {
+            SettingsMainScreen(
+                viewModel = viewModel,
+                onNavigate = { route -> navController.navigate(route.route) },
+                onBack = onFinish
+            )
+        }
+        
+        // Server Settings
+        composable(SettingsRoute.Server.route) {
+            ServerSettingsScreen(
+                viewModel = viewModel,
+                onBack = { navController.popBackStack() }
+            )
+        }
+        
+        // Sync Settings
+        composable(SettingsRoute.Sync.route) {
+            SyncSettingsScreen(
+                viewModel = viewModel,
+                onBack = { navController.popBackStack() }
+            )
+        }
+        
+        // Markdown Settings
+        composable(SettingsRoute.Markdown.route) {
+            MarkdownSettingsScreen(
+                viewModel = viewModel,
+                onBack = { navController.popBackStack() }
+            )
+        }
+        
+        // Backup Settings
+        composable(SettingsRoute.Backup.route) {
+            BackupSettingsScreen(
+                viewModel = viewModel,
+                onBack = { navController.popBackStack() }
+            )
+        }
+        
+        // About Screen
+        composable(SettingsRoute.About.route) {
+            AboutScreen(
+                onBack = { navController.popBackStack() }
+            )
+        }
+        
+        // Debug Settings
+        composable(SettingsRoute.Debug.route) {
+            DebugSettingsScreen(
+                viewModel = viewModel,
+                onBack = { navController.popBackStack() }
+            )
+        }
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/SettingsRoute.kt

@@ -0,0 +1,15 @@
+package dev.dettmer.simplenotes.ui.settings
+
+/**
+ * Navigation routes for Settings screens
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+sealed class SettingsRoute(val route: String) {
+    data object Main : SettingsRoute("settings_main")
+    data object Server : SettingsRoute("settings_server")
+    data object Sync : SettingsRoute("settings_sync")
+    data object Markdown : SettingsRoute("settings_markdown")
+    data object Backup : SettingsRoute("settings_backup")
+    data object About : SettingsRoute("settings_about")
+    data object Debug : SettingsRoute("settings_debug")
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/SettingsViewModel.kt

@@ -0,0 +1,493 @@
+package dev.dettmer.simplenotes.ui.settings
+
+import android.app.Application
+import android.content.Context
+import android.net.Uri
+import android.util.Log
+import androidx.lifecycle.AndroidViewModel
+import androidx.lifecycle.viewModelScope
+import dev.dettmer.simplenotes.backup.BackupManager
+import dev.dettmer.simplenotes.backup.RestoreMode
+import dev.dettmer.simplenotes.sync.WebDavSyncService
+import dev.dettmer.simplenotes.utils.Constants
+import dev.dettmer.simplenotes.utils.Logger
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharedFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asSharedFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import java.net.HttpURLConnection
+import java.net.URL
+
+/**
+ * ViewModel for Settings screens
+ * v1.5.0: Jetpack Compose Settings Redesign
+ * 
+ * Manages all settings state and actions across the Settings navigation graph.
+ */
+class SettingsViewModel(application: Application) : AndroidViewModel(application) {
+    
+    companion object {
+        private const val TAG = "SettingsViewModel"
+        private const val CONNECTION_TIMEOUT_MS = 3000
+    }
+    
+    private val prefs = application.getSharedPreferences(Constants.PREFS_NAME, Context.MODE_PRIVATE)
+    val backupManager = BackupManager(application)
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Server Settings State
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    // v1.5.0 Fix: Initialize URL with protocol prefix if empty
+    private val storedUrl = prefs.getString(Constants.KEY_SERVER_URL, "") ?: ""
+    private val initialUrl = if (storedUrl.isEmpty()) "http://" else storedUrl
+    
+    private val _serverUrl = MutableStateFlow(initialUrl)
+    val serverUrl: StateFlow<String> = _serverUrl.asStateFlow()
+    
+    private val _username = MutableStateFlow(prefs.getString(Constants.KEY_USERNAME, "") ?: "")
+    val username: StateFlow<String> = _username.asStateFlow()
+    
+    private val _password = MutableStateFlow(prefs.getString(Constants.KEY_PASSWORD, "") ?: "")
+    val password: StateFlow<String> = _password.asStateFlow()
+    
+    // v1.5.0 Fix: isHttps based on stored URL (false = HTTP if empty)
+    private val _isHttps = MutableStateFlow(storedUrl.startsWith("https://"))
+    val isHttps: StateFlow<Boolean> = _isHttps.asStateFlow()
+    
+    private val _serverStatus = MutableStateFlow<ServerStatus>(ServerStatus.Unknown)
+    val serverStatus: StateFlow<ServerStatus> = _serverStatus.asStateFlow()
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Events (for Activity-level actions like dialogs, intents)
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    private val _events = MutableSharedFlow<SettingsEvent>()
+    val events: SharedFlow<SettingsEvent> = _events.asSharedFlow()
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Markdown Export Progress State
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    private val _markdownExportProgress = MutableStateFlow<MarkdownExportProgress?>(null)
+    val markdownExportProgress: StateFlow<MarkdownExportProgress?> = _markdownExportProgress.asStateFlow()
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Sync Settings State
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    private val _autoSyncEnabled = MutableStateFlow(prefs.getBoolean(Constants.KEY_AUTO_SYNC, false))
+    val autoSyncEnabled: StateFlow<Boolean> = _autoSyncEnabled.asStateFlow()
+    
+    private val _syncInterval = MutableStateFlow(
+        prefs.getLong(Constants.PREF_SYNC_INTERVAL_MINUTES, Constants.DEFAULT_SYNC_INTERVAL_MINUTES)
+    )
+    val syncInterval: StateFlow<Long> = _syncInterval.asStateFlow()
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Markdown Settings State
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    private val _markdownAutoSync = MutableStateFlow(
+        prefs.getBoolean(Constants.KEY_MARKDOWN_EXPORT, false) &&
+        prefs.getBoolean(Constants.KEY_MARKDOWN_AUTO_IMPORT, false)
+    )
+    val markdownAutoSync: StateFlow<Boolean> = _markdownAutoSync.asStateFlow()
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Debug Settings State
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    private val _fileLoggingEnabled = MutableStateFlow(
+        prefs.getBoolean(Constants.KEY_FILE_LOGGING_ENABLED, false)
+    )
+    val fileLoggingEnabled: StateFlow<Boolean> = _fileLoggingEnabled.asStateFlow()
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // UI State
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    private val _isSyncing = MutableStateFlow(false)
+    val isSyncing: StateFlow<Boolean> = _isSyncing.asStateFlow()
+    
+    private val _isBackupInProgress = MutableStateFlow(false)
+    val isBackupInProgress: StateFlow<Boolean> = _isBackupInProgress.asStateFlow()
+    
+    private val _showToast = MutableSharedFlow<String>()
+    val showToast: SharedFlow<String> = _showToast.asSharedFlow()
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Server Settings Actions
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    fun updateServerUrl(url: String) {
+        _serverUrl.value = url
+        saveServerSettings()
+    }
+    
+    fun updateProtocol(useHttps: Boolean) {
+        _isHttps.value = useHttps
+        val currentUrl = _serverUrl.value
+        
+        // v1.5.0 Fix: Automatisch Prefix setzen, auch bei leerem Feld
+        val newUrl = if (useHttps) {
+            when {
+                currentUrl.isEmpty() || currentUrl == "http://" -> "https://"
+                currentUrl.startsWith("http://") -> currentUrl.replace("http://", "https://")
+                !currentUrl.startsWith("https://") -> "https://$currentUrl"
+                else -> currentUrl
+            }
+        } else {
+            when {
+                currentUrl.isEmpty() || currentUrl == "https://" -> "http://"
+                currentUrl.startsWith("https://") -> currentUrl.replace("https://", "http://")
+                !currentUrl.startsWith("http://") -> "http://$currentUrl"
+                else -> currentUrl
+            }
+        }
+        _serverUrl.value = newUrl
+        saveServerSettings()
+    }
+    
+    fun updateUsername(value: String) {
+        _username.value = value
+        saveServerSettings()
+    }
+    
+    fun updatePassword(value: String) {
+        _password.value = value
+        saveServerSettings()
+    }
+    
+    private fun saveServerSettings() {
+        prefs.edit().apply {
+            putString(Constants.KEY_SERVER_URL, _serverUrl.value)
+            putString(Constants.KEY_USERNAME, _username.value)
+            putString(Constants.KEY_PASSWORD, _password.value)
+            apply()
+        }
+    }
+    
+    fun testConnection() {
+        viewModelScope.launch {
+            _serverStatus.value = ServerStatus.Checking
+            try {
+                val syncService = WebDavSyncService(getApplication())
+                val result = syncService.testConnection()
+                _serverStatus.value = if (result.isSuccess) {
+                    ServerStatus.Reachable
+                } else {
+                    ServerStatus.Unreachable(result.errorMessage)
+                }
+                emitToast(if (result.isSuccess) "✅ Verbindung erfolgreich!" else "❌ ${result.errorMessage}")
+            } catch (e: Exception) {
+                _serverStatus.value = ServerStatus.Unreachable(e.message)
+                emitToast("❌ Fehler: ${e.message}")
+            }
+        }
+    }
+    
+    fun checkServerStatus() {
+        val serverUrl = _serverUrl.value
+        // v1.5.0 Fix: URL mit nur Prefix gilt als "nicht konfiguriert"
+        if (serverUrl.isEmpty() || serverUrl == "http://" || serverUrl == "https://") {
+            _serverStatus.value = ServerStatus.NotConfigured
+            return
+        }
+        
+        viewModelScope.launch {
+            _serverStatus.value = ServerStatus.Checking
+            val isReachable = withContext(Dispatchers.IO) {
+                try {
+                    val url = URL(serverUrl)
+                    val connection = url.openConnection() as HttpURLConnection
+                    connection.connectTimeout = CONNECTION_TIMEOUT_MS
+                    connection.readTimeout = CONNECTION_TIMEOUT_MS
+                    val code = connection.responseCode
+                    connection.disconnect()
+                    code in 200..299 || code == 401
+                } catch (e: Exception) {
+                    Log.e(TAG, "Server check failed: ${e.message}")
+                    false
+                }
+            }
+            _serverStatus.value = if (isReachable) ServerStatus.Reachable else ServerStatus.Unreachable(null)
+        }
+    }
+    
+    fun syncNow() {
+        if (_isSyncing.value) return
+        viewModelScope.launch {
+            _isSyncing.value = true
+            try {
+                emitToast("🔄 Synchronisiere...")
+                val syncService = WebDavSyncService(getApplication())
+                
+                if (!syncService.hasUnsyncedChanges()) {
+                    emitToast("✅ Bereits synchronisiert")
+                    return@launch
+                }
+                
+                val result = syncService.syncNotes()
+                if (result.isSuccess) {
+                    emitToast("✅ ${result.syncedCount} Notizen synchronisiert")
+                } else {
+                    emitToast("❌ ${result.errorMessage}")
+                }
+            } catch (e: Exception) {
+                emitToast("❌ Fehler: ${e.message}")
+            } finally {
+                _isSyncing.value = false
+            }
+        }
+    }
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Sync Settings Actions
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    fun setAutoSync(enabled: Boolean) {
+        _autoSyncEnabled.value = enabled
+        prefs.edit().putBoolean(Constants.KEY_AUTO_SYNC, enabled).apply()
+        
+        viewModelScope.launch {
+            if (enabled) {
+                // v1.5.0 Fix: Trigger battery optimization check and network monitor restart
+                _events.emit(SettingsEvent.RequestBatteryOptimization)
+                _events.emit(SettingsEvent.RestartNetworkMonitor)
+                emitToast("✅ Auto-Sync aktiviert")
+            } else {
+                _events.emit(SettingsEvent.RestartNetworkMonitor)
+                emitToast("Auto-Sync deaktiviert")
+            }
+        }
+    }
+    
+    fun setSyncInterval(minutes: Long) {
+        _syncInterval.value = minutes
+        prefs.edit().putLong(Constants.PREF_SYNC_INTERVAL_MINUTES, minutes).apply()
+        viewModelScope.launch {
+            val text = when (minutes) {
+                15L -> "15 Minuten"
+                60L -> "60 Minuten"
+                else -> "30 Minuten"
+            }
+            emitToast("⏱️ Sync-Intervall: $text")
+        }
+    }
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Markdown Settings Actions
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    fun setMarkdownAutoSync(enabled: Boolean) {
+        if (enabled) {
+            // v1.5.0 Fix: Perform initial export when enabling (like old SettingsActivity)
+            viewModelScope.launch {
+                try {
+                    // Check server configuration first
+                    val serverUrl = prefs.getString(Constants.KEY_SERVER_URL, "") ?: ""
+                    val username = prefs.getString(Constants.KEY_USERNAME, "") ?: ""
+                    val password = prefs.getString(Constants.KEY_PASSWORD, "") ?: ""
+                    
+                    if (serverUrl.isBlank() || username.isBlank() || password.isBlank()) {
+                        emitToast("⚠️ Bitte zuerst WebDAV-Server konfigurieren")
+                        // Don't enable - revert state
+                        return@launch
+                    }
+                    
+                    // Check if there are notes to export
+                    val noteStorage = dev.dettmer.simplenotes.storage.NotesStorage(getApplication())
+                    val noteCount = noteStorage.loadAllNotes().size
+                    
+                    if (noteCount > 0) {
+                        // Show progress and perform initial export
+                        _markdownExportProgress.value = MarkdownExportProgress(0, noteCount)
+                        
+                        val syncService = WebDavSyncService(getApplication())
+                        val exportedCount = withContext(Dispatchers.IO) {
+                            syncService.exportAllNotesToMarkdown(
+                                serverUrl = serverUrl,
+                                username = username,
+                                password = password,
+                                onProgress = { current, total ->
+                                    _markdownExportProgress.value = MarkdownExportProgress(current, total)
+                                }
+                            )
+                        }
+                        
+                        // Export successful - save settings
+                        _markdownAutoSync.value = true
+                        prefs.edit()
+                            .putBoolean(Constants.KEY_MARKDOWN_EXPORT, true)
+                            .putBoolean(Constants.KEY_MARKDOWN_AUTO_IMPORT, true)
+                            .apply()
+                        
+                        _markdownExportProgress.value = MarkdownExportProgress(noteCount, noteCount, isComplete = true)
+                        emitToast("✅ $exportedCount Notizen nach Markdown exportiert")
+                        
+                        // Clear progress after short delay
+                        kotlinx.coroutines.delay(500)
+                        _markdownExportProgress.value = null
+                        
+                    } else {
+                        // No notes - just enable the feature
+                        _markdownAutoSync.value = true
+                        prefs.edit()
+                            .putBoolean(Constants.KEY_MARKDOWN_EXPORT, true)
+                            .putBoolean(Constants.KEY_MARKDOWN_AUTO_IMPORT, true)
+                            .apply()
+                        emitToast("📝 Markdown Auto-Sync aktiviert")
+                    }
+                    
+                } catch (e: Exception) {
+                    _markdownExportProgress.value = null
+                    emitToast("❌ Export fehlgeschlagen: ${e.message}")
+                    // Don't enable on error
+                }
+            }
+        } else {
+            // Disable - simple
+            _markdownAutoSync.value = false
+            prefs.edit()
+                .putBoolean(Constants.KEY_MARKDOWN_EXPORT, false)
+                .putBoolean(Constants.KEY_MARKDOWN_AUTO_IMPORT, false)
+                .apply()
+            viewModelScope.launch {
+                emitToast("📝 Markdown Auto-Sync deaktiviert")
+            }
+        }
+    }
+    
+    fun performManualMarkdownSync() {
+        viewModelScope.launch {
+            try {
+                emitToast("📝 Markdown-Sync läuft...")
+                val syncService = WebDavSyncService(getApplication())
+                val result = syncService.manualMarkdownSync()
+                emitToast("✅ Export: ${result.exportedCount} • Import: ${result.importedCount}")
+            } catch (e: Exception) {
+                emitToast("❌ Fehler: ${e.message}")
+            }
+        }
+    }
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Backup Actions
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    fun createBackup(uri: Uri) {
+        viewModelScope.launch {
+            _isBackupInProgress.value = true
+            try {
+                val result = backupManager.createBackup(uri)
+                emitToast(if (result.success) "✅ ${result.message}" else "❌ ${result.error}")
+            } catch (e: Exception) {
+                emitToast("❌ Backup fehlgeschlagen: ${e.message}")
+            } finally {
+                _isBackupInProgress.value = false
+            }
+        }
+    }
+    
+    fun restoreFromFile(uri: Uri, mode: RestoreMode) {
+        viewModelScope.launch {
+            _isBackupInProgress.value = true
+            try {
+                val result = backupManager.restoreBackup(uri, mode)
+                emitToast(if (result.success) "✅ ${result.importedNotes} Notizen wiederhergestellt" else "❌ ${result.error}")
+            } catch (e: Exception) {
+                emitToast("❌ Wiederherstellung fehlgeschlagen: ${e.message}")
+            } finally {
+                _isBackupInProgress.value = false
+            }
+        }
+    }
+    
+    fun restoreFromServer(mode: RestoreMode) {
+        viewModelScope.launch {
+            _isBackupInProgress.value = true
+            try {
+                emitToast("📥 Lade vom Server...")
+                val syncService = WebDavSyncService(getApplication())
+                val result = withContext(Dispatchers.IO) {
+                    syncService.restoreFromServer(mode)
+                }
+                emitToast(if (result.isSuccess) "✅ ${result.restoredCount} Notizen wiederhergestellt" else "❌ ${result.errorMessage}")
+            } catch (e: Exception) {
+                emitToast("❌ Fehler: ${e.message}")
+            } finally {
+                _isBackupInProgress.value = false
+            }
+        }
+    }
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Debug Settings Actions
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    fun setFileLogging(enabled: Boolean) {
+        _fileLoggingEnabled.value = enabled
+        prefs.edit().putBoolean(Constants.KEY_FILE_LOGGING_ENABLED, enabled).apply()
+        Logger.setFileLoggingEnabled(enabled)
+        viewModelScope.launch {
+            emitToast(if (enabled) "📝 Datei-Logging aktiviert" else "📝 Datei-Logging deaktiviert")
+        }
+    }
+    
+    fun clearLogs() {
+        viewModelScope.launch {
+            try {
+                val cleared = Logger.clearLogFile(getApplication())
+                emitToast(if (cleared) "🗑️ Logs gelöscht" else "📭 Keine Logs zum Löschen")
+            } catch (e: Exception) {
+                emitToast("❌ Fehler: ${e.message}")
+            }
+        }
+    }
+    
+    fun getLogFile() = Logger.getLogFile(getApplication())
+    
+    // ═══════════════════════════════════════════════════════════════════════
+    // Helper
+    // ═══════════════════════════════════════════════════════════════════════
+    
+    private suspend fun emitToast(message: String) {
+        _showToast.emit(message)
+    }
+    
+    /**
+     * Server status states
+     */
+    sealed class ServerStatus {
+        data object Unknown : ServerStatus()
+        data object NotConfigured : ServerStatus()
+        data object Checking : ServerStatus()
+        data object Reachable : ServerStatus()
+        data class Unreachable(val error: String?) : ServerStatus()
+    }
+    
+    /**
+     * Events for Activity-level actions (dialogs, intents, etc.)
+     * v1.5.0: Ported from old SettingsActivity
+     */
+    sealed class SettingsEvent {
+        data object RequestBatteryOptimization : SettingsEvent()
+        data object RestartNetworkMonitor : SettingsEvent()
+    }
+    
+    /**
+     * Progress state for Markdown export
+     * v1.5.0: For initial export progress dialog
+     */
+    data class MarkdownExportProgress(
+        val current: Int,
+        val total: Int,
+        val isComplete: Boolean = false
+    )
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/components/SettingsCard.kt

@@ -0,0 +1,113 @@
+package dev.dettmer.simplenotes.ui.settings.components
+
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.KeyboardArrowRight
+import androidx.compose.material3.Card
+import androidx.compose.material3.CardDefaults
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.unit.dp
+
+/**
+ * Clickable Settings group card with icon, title, subtitle and optional status
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun SettingsCard(
+    icon: ImageVector,
+    title: String,
+    modifier: Modifier = Modifier,
+    subtitle: String? = null,
+    statusText: String? = null,
+    statusColor: Color = MaterialTheme.colorScheme.onSurfaceVariant,
+    onClick: () -> Unit
+) {
+    Card(
+        modifier = modifier
+            .fillMaxWidth()
+            .padding(horizontal = 16.dp, vertical = 4.dp)
+            .clickable(onClick = onClick),
+        shape = RoundedCornerShape(16.dp),
+        colors = CardDefaults.cardColors(
+            containerColor = MaterialTheme.colorScheme.surfaceContainerHigh
+        )
+    ) {
+        Row(
+            modifier = Modifier
+                .fillMaxWidth()
+                .padding(16.dp),
+            verticalAlignment = Alignment.CenterVertically
+        ) {
+            // Icon with circle background
+            Box(
+                modifier = Modifier
+                    .size(40.dp)
+                    .background(
+                        color = MaterialTheme.colorScheme.primaryContainer,
+                        shape = CircleShape
+                    ),
+                contentAlignment = Alignment.Center
+            ) {
+                Icon(
+                    imageVector = icon,
+                    contentDescription = null,
+                    tint = MaterialTheme.colorScheme.onPrimaryContainer,
+                    modifier = Modifier.size(20.dp)
+                )
+            }
+            
+            Spacer(modifier = Modifier.width(16.dp))
+            
+            // Content
+            Column(modifier = Modifier.weight(1f)) {
+                Text(
+                    text = title,
+                    style = MaterialTheme.typography.titleMedium,
+                    color = MaterialTheme.colorScheme.onSurface
+                )
+                if (subtitle != null) {
+                    Spacer(modifier = Modifier.height(2.dp))
+                    Text(
+                        text = subtitle,
+                        style = MaterialTheme.typography.bodyMedium,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant
+                    )
+                }
+                if (statusText != null) {
+                    Spacer(modifier = Modifier.height(2.dp))
+                    Text(
+                        text = statusText,
+                        style = MaterialTheme.typography.bodySmall,
+                        color = statusColor
+                    )
+                }
+            }
+            
+            // Arrow
+            Icon(
+                imageVector = Icons.AutoMirrored.Filled.KeyboardArrowRight,
+                contentDescription = null,
+                tint = MaterialTheme.colorScheme.onSurfaceVariant
+            )
+        }
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/components/SettingsComponents.kt

@@ -0,0 +1,152 @@
+package dev.dettmer.simplenotes.ui.settings.components
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+
+/**
+ * Primary filled button for settings actions
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun SettingsButton(
+    text: String,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    isLoading: Boolean = false
+) {
+    Button(
+        onClick = onClick,
+        enabled = enabled && !isLoading,
+        modifier = modifier.fillMaxWidth()
+    ) {
+        if (isLoading) {
+            CircularProgressIndicator(
+                modifier = Modifier.height(20.dp),
+                strokeWidth = 2.dp,
+                color = MaterialTheme.colorScheme.onPrimary
+            )
+        } else {
+            Text(text)
+        }
+    }
+}
+
+/**
+ * Outlined secondary button for settings actions
+ */
+@Composable
+fun SettingsOutlinedButton(
+    text: String,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    isLoading: Boolean = false
+) {
+    OutlinedButton(
+        onClick = onClick,
+        enabled = enabled && !isLoading,
+        modifier = modifier.fillMaxWidth()
+    ) {
+        if (isLoading) {
+            CircularProgressIndicator(
+                modifier = Modifier.height(20.dp),
+                strokeWidth = 2.dp,
+                color = MaterialTheme.colorScheme.primary
+            )
+        } else {
+            Text(text)
+        }
+    }
+}
+
+/**
+ * Danger/destructive button for settings actions
+ */
+@Composable
+fun SettingsDangerButton(
+    text: String,
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true
+) {
+    OutlinedButton(
+        onClick = onClick,
+        enabled = enabled,
+        modifier = modifier.fillMaxWidth(),
+        colors = ButtonDefaults.outlinedButtonColors(
+            contentColor = MaterialTheme.colorScheme.error
+        )
+    ) {
+        Text(text)
+    }
+}
+
+/**
+ * Info card with description text
+ */
+@Composable
+fun SettingsInfoCard(
+    text: String,
+    modifier: Modifier = Modifier
+) {
+    androidx.compose.material3.Card(
+        modifier = modifier
+            .fillMaxWidth()
+            .padding(horizontal = 16.dp, vertical = 8.dp),
+        colors = androidx.compose.material3.CardDefaults.cardColors(
+            containerColor = MaterialTheme.colorScheme.surfaceContainerHighest
+        )
+    ) {
+        Text(
+            text = text,
+            style = MaterialTheme.typography.bodySmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+            modifier = Modifier.padding(16.dp),
+            lineHeight = MaterialTheme.typography.bodySmall.lineHeight * 1.3f
+        )
+    }
+}
+
+/**
+ * Section header text
+ */
+@Composable
+fun SettingsSectionHeader(
+    text: String,
+    modifier: Modifier = Modifier
+) {
+    Text(
+        text = text,
+        style = MaterialTheme.typography.labelLarge,
+        color = MaterialTheme.colorScheme.primary,
+        modifier = modifier.padding(horizontal = 16.dp, vertical = 8.dp)
+    )
+}
+
+/**
+ * Divider between settings groups
+ */
+@Composable
+fun SettingsDivider(
+    modifier: Modifier = Modifier
+) {
+    Spacer(modifier = modifier.height(8.dp))
+    androidx.compose.material3.HorizontalDivider(
+        modifier = Modifier.padding(horizontal = 16.dp),
+        color = MaterialTheme.colorScheme.outlineVariant
+    )
+    Spacer(modifier = Modifier.height(8.dp))
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/components/SettingsRadioGroup.kt

@@ -0,0 +1,94 @@
+package dev.dettmer.simplenotes.ui.settings.components
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.selection.selectable
+import androidx.compose.foundation.selection.selectableGroup
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.RadioButton
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.semantics.Role
+import androidx.compose.ui.unit.dp
+
+/**
+ * Data class for radio option
+ */
+data class RadioOption<T>(
+    val value: T,
+    val title: String,
+    val subtitle: String? = null
+)
+
+/**
+ * Settings radio group for selecting one option
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun <T> SettingsRadioGroup(
+    options: List<RadioOption<T>>,
+    selectedValue: T,
+    onValueSelected: (T) -> Unit,
+    modifier: Modifier = Modifier,
+    title: String? = null
+) {
+    Column(
+        modifier = modifier
+            .fillMaxWidth()
+            .selectableGroup()
+    ) {
+        if (title != null) {
+            Text(
+                text = title,
+                style = MaterialTheme.typography.labelLarge,
+                color = MaterialTheme.colorScheme.primary,
+                modifier = Modifier.padding(horizontal = 16.dp, vertical = 8.dp)
+            )
+        }
+        
+        options.forEach { option ->
+            Row(
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .selectable(
+                        selected = option.value == selectedValue,
+                        onClick = { onValueSelected(option.value) },
+                        role = Role.RadioButton
+                    )
+                    .padding(horizontal = 16.dp, vertical = 12.dp),
+                verticalAlignment = Alignment.CenterVertically
+            ) {
+                RadioButton(
+                    selected = option.value == selectedValue,
+                    onClick = null // handled by selectable
+                )
+                
+                Column(
+                    modifier = Modifier
+                        .padding(start = 16.dp)
+                        .weight(1f)
+                ) {
+                    Text(
+                        text = option.title,
+                        style = MaterialTheme.typography.bodyLarge,
+                        color = MaterialTheme.colorScheme.onSurface
+                    )
+                    if (option.subtitle != null) {
+                        Spacer(modifier = Modifier.height(2.dp))
+                        Text(
+                            text = option.subtitle,
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant
+                        )
+                    }
+                }
+            }
+        }
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/components/SettingsScaffold.kt

@@ -0,0 +1,57 @@
+package dev.dettmer.simplenotes.ui.settings.components
+
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.material3.TopAppBarDefaults
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+
+/**
+ * Reusable Scaffold with back-navigation TopAppBar
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun SettingsScaffold(
+    title: String,
+    onBack: () -> Unit,
+    modifier: Modifier = Modifier,
+    content: @Composable (PaddingValues) -> Unit
+) {
+    Scaffold(
+        modifier = modifier,
+        topBar = {
+            TopAppBar(
+                title = {
+                    Text(
+                        text = title,
+                        style = MaterialTheme.typography.titleLarge
+                    )
+                },
+                navigationIcon = {
+                    IconButton(onClick = onBack) {
+                        Icon(
+                            imageVector = Icons.AutoMirrored.Filled.ArrowBack,
+                            contentDescription = "Zurück"
+                        )
+                    }
+                },
+                colors = TopAppBarDefaults.topAppBarColors(
+                    containerColor = MaterialTheme.colorScheme.surface,
+                    titleContentColor = MaterialTheme.colorScheme.onSurface
+                )
+            )
+        },
+        containerColor = MaterialTheme.colorScheme.surface
+    ) { paddingValues ->
+        content(paddingValues)
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/components/SettingsSwitch.kt

@@ -0,0 +1,83 @@
+package dev.dettmer.simplenotes.ui.settings.components
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Switch
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.unit.dp
+
+/**
+ * Settings switch item with title, optional subtitle and icon
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun SettingsSwitch(
+    title: String,
+    checked: Boolean,
+    onCheckedChange: (Boolean) -> Unit,
+    modifier: Modifier = Modifier,
+    subtitle: String? = null,
+    icon: ImageVector? = null,
+    enabled: Boolean = true
+) {
+    Row(
+        modifier = modifier
+            .fillMaxWidth()
+            .padding(horizontal = 16.dp, vertical = 12.dp),
+        verticalAlignment = Alignment.CenterVertically
+    ) {
+        if (icon != null) {
+            Icon(
+                imageVector = icon,
+                contentDescription = null,
+                tint = if (enabled) {
+                    MaterialTheme.colorScheme.onSurfaceVariant
+                } else {
+                    MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.38f)
+                },
+                modifier = Modifier.size(24.dp)
+            )
+            Spacer(modifier = Modifier.width(16.dp))
+        }
+        
+        Column(modifier = Modifier.weight(1f)) {
+            Text(
+                text = title,
+                style = MaterialTheme.typography.bodyLarge,
+                color = if (enabled) {
+                    MaterialTheme.colorScheme.onSurface
+                } else {
+                    MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f)
+                }
+            )
+            if (subtitle != null) {
+                Text(
+                    text = subtitle,
+                    style = MaterialTheme.typography.bodyMedium,
+                    color = if (enabled) {
+                        MaterialTheme.colorScheme.onSurfaceVariant
+                    } else {
+                        MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.38f)
+                    }
+                )
+            }
+        }
+        
+        Switch(
+            checked = checked,
+            onCheckedChange = onCheckedChange,
+            enabled = enabled
+        )
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/screens/AboutScreen.kt

@@ -0,0 +1,218 @@
+package dev.dettmer.simplenotes.ui.settings.screens
+
+import android.content.Intent
+import android.net.Uri
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.KeyboardArrowRight
+import androidx.compose.material.icons.filled.Code
+import androidx.compose.material.icons.filled.Person
+import androidx.compose.material.icons.filled.Policy
+import androidx.compose.material3.Card
+import androidx.compose.material3.CardDefaults
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.unit.dp
+import dev.dettmer.simplenotes.BuildConfig
+import dev.dettmer.simplenotes.ui.settings.components.SettingsDivider
+import dev.dettmer.simplenotes.ui.settings.components.SettingsScaffold
+import dev.dettmer.simplenotes.ui.settings.components.SettingsSectionHeader
+
+/**
+ * About app information screen
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun AboutScreen(
+    onBack: () -> Unit
+) {
+    val context = LocalContext.current
+    
+    val githubRepoUrl = "https://github.com/inventory69/simple-notes-sync"
+    val githubProfileUrl = "https://github.com/inventory69"
+    val licenseUrl = "https://github.com/inventory69/simple-notes-sync/blob/main/LICENSE"
+    
+    SettingsScaffold(
+        title = "Über diese App",
+        onBack = onBack
+    ) { paddingValues ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues)
+                .verticalScroll(rememberScrollState())
+        ) {
+            Spacer(modifier = Modifier.height(16.dp))
+            
+            // App Info Card
+            Card(
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .padding(horizontal = 16.dp),
+                colors = CardDefaults.cardColors(
+                    containerColor = MaterialTheme.colorScheme.primaryContainer
+                )
+            ) {
+                Column(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .padding(24.dp),
+                    horizontalAlignment = Alignment.CenterHorizontally
+                ) {
+                    Text(
+                        text = "📝",
+                        style = MaterialTheme.typography.displayMedium
+                    )
+                    
+                    Spacer(modifier = Modifier.height(8.dp))
+                    
+                    Text(
+                        text = "Simple Notes Sync",
+                        style = MaterialTheme.typography.headlineSmall,
+                        color = MaterialTheme.colorScheme.onPrimaryContainer
+                    )
+                    
+                    Spacer(modifier = Modifier.height(4.dp))
+                    
+                    Text(
+                        text = "Version ${BuildConfig.VERSION_NAME} (${BuildConfig.VERSION_CODE})",
+                        style = MaterialTheme.typography.bodyMedium,
+                        color = MaterialTheme.colorScheme.onPrimaryContainer.copy(alpha = 0.8f)
+                    )
+                }
+            }
+            
+            Spacer(modifier = Modifier.height(24.dp))
+            
+            SettingsSectionHeader(text = "Links")
+            
+            // GitHub Repository
+            AboutLinkItem(
+                icon = Icons.Default.Code,
+                title = "GitHub Repository",
+                subtitle = "Quellcode, Issues & Dokumentation",
+                onClick = {
+                    val intent = Intent(Intent.ACTION_VIEW, Uri.parse(githubRepoUrl))
+                    context.startActivity(intent)
+                }
+            )
+            
+            // Developer
+            AboutLinkItem(
+                icon = Icons.Default.Person,
+                title = "Entwickler",
+                subtitle = "GitHub Profil: @inventory69",
+                onClick = {
+                    val intent = Intent(Intent.ACTION_VIEW, Uri.parse(githubProfileUrl))
+                    context.startActivity(intent)
+                }
+            )
+            
+            // License
+            AboutLinkItem(
+                icon = Icons.Default.Policy,
+                title = "Lizenz",
+                subtitle = "MIT License - Open Source",
+                onClick = {
+                    val intent = Intent(Intent.ACTION_VIEW, Uri.parse(licenseUrl))
+                    context.startActivity(intent)
+                }
+            )
+            
+            SettingsDivider()
+            
+            // Data Privacy Info
+            Card(
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .padding(horizontal = 16.dp),
+                colors = CardDefaults.cardColors(
+                    containerColor = MaterialTheme.colorScheme.surfaceContainerHighest
+                )
+            ) {
+                Column(
+                    modifier = Modifier.padding(16.dp)
+                ) {
+                    Text(
+                        text = "🔒 Datenschutz",
+                        style = MaterialTheme.typography.titleSmall
+                    )
+                    Spacer(modifier = Modifier.height(8.dp))
+                    Text(
+                        text = "Diese App sammelt keine Daten. Alle Notizen werden " +
+                            "nur lokal auf deinem Gerät und auf deinem eigenen " +
+                            "WebDAV-Server gespeichert. Keine Telemetrie, keine Werbung.",
+                        style = MaterialTheme.typography.bodySmall,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant
+                    )
+                }
+            }
+            
+            Spacer(modifier = Modifier.height(16.dp))
+        }
+    }
+}
+
+/**
+ * Clickable link item for About section
+ */
+@Composable
+private fun AboutLinkItem(
+    icon: ImageVector,
+    title: String,
+    subtitle: String,
+    onClick: () -> Unit
+) {
+    Row(
+        modifier = Modifier
+            .fillMaxWidth()
+            .clickable(onClick = onClick)
+            .padding(horizontal = 16.dp, vertical = 12.dp),
+        verticalAlignment = Alignment.CenterVertically
+    ) {
+        Icon(
+            imageVector = icon,
+            contentDescription = null,
+            tint = MaterialTheme.colorScheme.primary,
+            modifier = Modifier.size(24.dp)
+        )
+        
+        Spacer(modifier = Modifier.width(16.dp))
+        
+        Column(modifier = Modifier.weight(1f)) {
+            Text(
+                text = title,
+                style = MaterialTheme.typography.bodyLarge,
+                color = MaterialTheme.colorScheme.onSurface
+            )
+            Text(
+                text = subtitle,
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant
+            )
+        }
+        
+        Icon(
+            imageVector = Icons.AutoMirrored.Filled.KeyboardArrowRight,
+            contentDescription = null,
+            tint = MaterialTheme.colorScheme.onSurfaceVariant
+        )
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/screens/BackupSettingsScreen.kt

@@ -0,0 +1,256 @@
+package dev.dettmer.simplenotes.ui.settings.screens
+
+import android.net.Uri
+import androidx.activity.compose.rememberLauncherForActivityResult
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import dev.dettmer.simplenotes.backup.RestoreMode
+import dev.dettmer.simplenotes.ui.settings.SettingsViewModel
+import dev.dettmer.simplenotes.ui.settings.components.RadioOption
+import dev.dettmer.simplenotes.ui.settings.components.SettingsButton
+import dev.dettmer.simplenotes.ui.settings.components.SettingsDivider
+import dev.dettmer.simplenotes.ui.settings.components.SettingsInfoCard
+import dev.dettmer.simplenotes.ui.settings.components.SettingsOutlinedButton
+import dev.dettmer.simplenotes.ui.settings.components.SettingsRadioGroup
+import dev.dettmer.simplenotes.ui.settings.components.SettingsScaffold
+import dev.dettmer.simplenotes.ui.settings.components.SettingsSectionHeader
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+
+/**
+ * Backup and restore settings screen
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun BackupSettingsScreen(
+    viewModel: SettingsViewModel,
+    onBack: () -> Unit
+) {
+    val isBackupInProgress by viewModel.isBackupInProgress.collectAsState()
+    
+    // Restore dialog state
+    var showRestoreDialog by remember { mutableStateOf(false) }
+    var restoreSource by remember { mutableStateOf<RestoreSource>(RestoreSource.LocalFile) }
+    var pendingRestoreUri by remember { mutableStateOf<Uri?>(null) }
+    var selectedRestoreMode by remember { mutableStateOf(RestoreMode.MERGE) }
+    
+    // File picker launchers
+    val createBackupLauncher = rememberLauncherForActivityResult(
+        contract = ActivityResultContracts.CreateDocument("application/json")
+    ) { uri ->
+        uri?.let { viewModel.createBackup(it) }
+    }
+    
+    val restoreFileLauncher = rememberLauncherForActivityResult(
+        contract = ActivityResultContracts.OpenDocument()
+    ) { uri ->
+        uri?.let {
+            pendingRestoreUri = it
+            restoreSource = RestoreSource.LocalFile
+            showRestoreDialog = true
+        }
+    }
+    
+    SettingsScaffold(
+        title = "Backup & Wiederherstellung",
+        onBack = onBack
+    ) { paddingValues ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues)
+                .verticalScroll(rememberScrollState())
+        ) {
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // Info Card
+            SettingsInfoCard(
+                text = "📦 Bei jeder Wiederherstellung wird automatisch ein " +
+                    "Sicherheits-Backup erstellt."
+            )
+            
+            Spacer(modifier = Modifier.height(16.dp))
+            
+            // Local Backup Section
+            SettingsSectionHeader(text = "Lokales Backup")
+            
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            SettingsButton(
+                text = "💾 Backup erstellen",
+                onClick = {
+                    val timestamp = SimpleDateFormat("yyyy-MM-dd_HHmmss", Locale.US)
+                        .format(Date())
+                    val filename = "simplenotes_backup_$timestamp.json"
+                    createBackupLauncher.launch(filename)
+                },
+                isLoading = isBackupInProgress,
+                modifier = Modifier.padding(horizontal = 16.dp)
+            )
+            
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            SettingsOutlinedButton(
+                text = "📂 Aus Datei wiederherstellen",
+                onClick = {
+                    restoreFileLauncher.launch(arrayOf("application/json"))
+                },
+                isLoading = isBackupInProgress,
+                modifier = Modifier.padding(horizontal = 16.dp)
+            )
+            
+            SettingsDivider()
+            
+            // Server Backup Section
+            SettingsSectionHeader(text = "Server-Backup")
+            
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            SettingsOutlinedButton(
+                text = "☁️ Vom Server wiederherstellen",
+                onClick = {
+                    restoreSource = RestoreSource.Server
+                    showRestoreDialog = true
+                },
+                isLoading = isBackupInProgress,
+                modifier = Modifier.padding(horizontal = 16.dp)
+            )
+            
+            Spacer(modifier = Modifier.height(16.dp))
+        }
+    }
+    
+    // Restore Mode Dialog
+    if (showRestoreDialog) {
+        RestoreModeDialog(
+            source = restoreSource,
+            selectedMode = selectedRestoreMode,
+            onModeSelected = { selectedRestoreMode = it },
+            onConfirm = {
+                showRestoreDialog = false
+                when (restoreSource) {
+                    RestoreSource.LocalFile -> {
+                        pendingRestoreUri?.let { uri ->
+                            viewModel.restoreFromFile(uri, selectedRestoreMode)
+                        }
+                    }
+                    RestoreSource.Server -> {
+                        viewModel.restoreFromServer(selectedRestoreMode)
+                    }
+                }
+            },
+            onDismiss = {
+                showRestoreDialog = false
+                pendingRestoreUri = null
+            }
+        )
+    }
+}
+
+/**
+ * Restore source enum
+ */
+private enum class RestoreSource {
+    LocalFile,
+    Server
+}
+
+/**
+ * Dialog for selecting restore mode
+ */
+@Composable
+private fun RestoreModeDialog(
+    source: RestoreSource,
+    selectedMode: RestoreMode,
+    onModeSelected: (RestoreMode) -> Unit,
+    onConfirm: () -> Unit,
+    onDismiss: () -> Unit
+) {
+    val sourceText = when (source) {
+        RestoreSource.LocalFile -> "Lokale Datei"
+        RestoreSource.Server -> "WebDAV Server"
+    }
+    
+    val modeOptions = listOf(
+        RadioOption(
+            value = RestoreMode.MERGE,
+            title = "⚪ Zusammenführen (Standard)",
+            subtitle = "Neue hinzufügen, Bestehende behalten"
+        ),
+        RadioOption(
+            value = RestoreMode.REPLACE,
+            title = "⚪ Ersetzen",
+            subtitle = "Alle löschen & Backup importieren"
+        ),
+        RadioOption(
+            value = RestoreMode.OVERWRITE_DUPLICATES,
+            title = "⚪ Duplikate überschreiben",
+            subtitle = "Backup gewinnt bei Konflikten"
+        )
+    )
+    
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text("⚠️ Backup wiederherstellen?") },
+        text = {
+            Column {
+                Text(
+                    text = "Quelle: $sourceText",
+                    style = MaterialTheme.typography.bodyMedium
+                )
+                
+                Spacer(modifier = Modifier.height(16.dp))
+                
+                Text(
+                    text = "Wiederherstellungs-Modus:",
+                    style = MaterialTheme.typography.labelLarge
+                )
+                
+                Spacer(modifier = Modifier.height(8.dp))
+                
+                SettingsRadioGroup(
+                    options = modeOptions,
+                    selectedValue = selectedMode,
+                    onValueSelected = onModeSelected
+                )
+                
+                Spacer(modifier = Modifier.height(8.dp))
+                
+                Text(
+                    text = "ℹ️ Ein Sicherheits-Backup wird vor dem Wiederherstellen automatisch erstellt.",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant
+                )
+            }
+        },
+        confirmButton = {
+            TextButton(onClick = onConfirm) {
+                Text("Wiederherstellen")
+            }
+        },
+        dismissButton = {
+            TextButton(onClick = onDismiss) {
+                Text("Abbrechen")
+            }
+        }
+    )
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/screens/DebugSettingsScreen.kt

@@ -0,0 +1,148 @@
+package dev.dettmer.simplenotes.ui.settings.screens
+
+import android.content.Intent
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.Notes
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.unit.dp
+import androidx.core.content.FileProvider
+import dev.dettmer.simplenotes.BuildConfig
+import dev.dettmer.simplenotes.ui.settings.SettingsViewModel
+import dev.dettmer.simplenotes.ui.settings.components.SettingsButton
+import dev.dettmer.simplenotes.ui.settings.components.SettingsDangerButton
+import dev.dettmer.simplenotes.ui.settings.components.SettingsDivider
+import dev.dettmer.simplenotes.ui.settings.components.SettingsInfoCard
+import dev.dettmer.simplenotes.ui.settings.components.SettingsScaffold
+import dev.dettmer.simplenotes.ui.settings.components.SettingsSectionHeader
+import dev.dettmer.simplenotes.ui.settings.components.SettingsSwitch
+
+/**
+ * Debug and diagnostics settings screen
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun DebugSettingsScreen(
+    viewModel: SettingsViewModel,
+    onBack: () -> Unit
+) {
+    val context = LocalContext.current
+    val fileLoggingEnabled by viewModel.fileLoggingEnabled.collectAsState()
+    
+    var showClearLogsDialog by remember { mutableStateOf(false) }
+    
+    SettingsScaffold(
+        title = "Debug & Diagnose",
+        onBack = onBack
+    ) { paddingValues ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues)
+                .verticalScroll(rememberScrollState())
+        ) {
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // File Logging Toggle
+            SettingsSwitch(
+                title = "Datei-Logging",
+                subtitle = "Sync-Logs in Datei speichern",
+                checked = fileLoggingEnabled,
+                onCheckedChange = { viewModel.setFileLogging(it) },
+                icon = Icons.AutoMirrored.Filled.Notes
+            )
+            
+            // Privacy Info
+            SettingsInfoCard(
+                text = "🔒 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."
+            )
+            
+            SettingsDivider()
+            
+            SettingsSectionHeader(text = "Log-Aktionen")
+            
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // Export Logs Button
+            SettingsButton(
+                text = "📤 Logs exportieren & teilen",
+                onClick = {
+                    val logFile = viewModel.getLogFile()
+                    if (logFile != null && logFile.exists() && logFile.length() > 0L) {
+                        val logUri = FileProvider.getUriForFile(
+                            context,
+                            "${BuildConfig.APPLICATION_ID}.fileprovider",
+                            logFile
+                        )
+                        
+                        val shareIntent = Intent(Intent.ACTION_SEND).apply {
+                            type = "text/plain"
+                            putExtra(Intent.EXTRA_STREAM, logUri)
+                            putExtra(Intent.EXTRA_SUBJECT, "SimpleNotes Sync Logs")
+                            addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
+                        }
+                        
+                        context.startActivity(Intent.createChooser(shareIntent, "Logs teilen via..."))
+                    }
+                },
+                modifier = Modifier.padding(horizontal = 16.dp)
+            )
+            
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // Clear Logs Button
+            SettingsDangerButton(
+                text = "🗑️ Logs löschen",
+                onClick = { showClearLogsDialog = true },
+                modifier = Modifier.padding(horizontal = 16.dp)
+            )
+            
+            Spacer(modifier = Modifier.height(16.dp))
+        }
+    }
+    
+    // Clear Logs Confirmation Dialog
+    if (showClearLogsDialog) {
+        AlertDialog(
+            onDismissRequest = { showClearLogsDialog = false },
+            title = { Text("Logs löschen?") },
+            text = {
+                Text("Alle gespeicherten Sync-Logs werden unwiderruflich gelöscht.")
+            },
+            confirmButton = {
+                TextButton(
+                    onClick = {
+                        showClearLogsDialog = false
+                        viewModel.clearLogs()
+                    }
+                ) {
+                    Text("Löschen")
+                }
+            },
+            dismissButton = {
+                TextButton(onClick = { showClearLogsDialog = false }) {
+                    Text("Abbrechen")
+                }
+            }
+        )
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/screens/MarkdownSettingsScreen.kt

@@ -0,0 +1,128 @@
+package dev.dettmer.simplenotes.ui.settings.screens
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Description
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.LinearProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import dev.dettmer.simplenotes.ui.settings.SettingsViewModel
+import dev.dettmer.simplenotes.ui.settings.components.SettingsButton
+import dev.dettmer.simplenotes.ui.settings.components.SettingsDivider
+import dev.dettmer.simplenotes.ui.settings.components.SettingsInfoCard
+import dev.dettmer.simplenotes.ui.settings.components.SettingsScaffold
+import dev.dettmer.simplenotes.ui.settings.components.SettingsSwitch
+
+/**
+ * Markdown Desktop integration settings screen
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun MarkdownSettingsScreen(
+    viewModel: SettingsViewModel,
+    onBack: () -> Unit
+) {
+    val markdownAutoSync by viewModel.markdownAutoSync.collectAsState()
+    val exportProgress by viewModel.markdownExportProgress.collectAsState()
+    
+    // v1.5.0 Fix: Progress Dialog for initial export
+    exportProgress?.let { progress ->
+        AlertDialog(
+            onDismissRequest = { /* Not dismissable */ },
+            title = { Text("Markdown Auto-Sync") },
+            text = {
+                Column(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalAlignment = Alignment.CenterHorizontally,
+                    verticalArrangement = Arrangement.spacedBy(12.dp)
+                ) {
+                    Text(
+                        text = if (progress.isComplete) {
+                            "✅ Export abgeschlossen"
+                        } else {
+                            "Exportiere ${progress.current}/${progress.total} Notizen..."
+                        },
+                        style = MaterialTheme.typography.bodyMedium
+                    )
+                    
+                    LinearProgressIndicator(
+                        progress = { 
+                            if (progress.total > 0) {
+                                progress.current.toFloat() / progress.total.toFloat()
+                            } else 0f
+                        },
+                        modifier = Modifier.fillMaxWidth()
+                    )
+                }
+            },
+            confirmButton = { /* No button - auto dismiss */ }
+        )
+    }
+    
+    SettingsScaffold(
+        title = "Markdown Desktop-Integration",
+        onBack = onBack
+    ) { paddingValues ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues)
+                .verticalScroll(rememberScrollState())
+        ) {
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // Info Card
+            SettingsInfoCard(
+                text = "📝 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."
+            )
+            
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // Markdown Auto-Sync Toggle
+            SettingsSwitch(
+                title = "Markdown Auto-Sync",
+                subtitle = "Synchronisiert Notizen automatisch als .md-Dateien (Upload + Download bei jedem Sync)",
+                checked = markdownAutoSync,
+                onCheckedChange = { viewModel.setMarkdownAutoSync(it) },
+                icon = Icons.Default.Description
+            )
+            
+            // Manual sync button (only visible when auto-sync is off)
+            if (!markdownAutoSync) {
+                SettingsDivider()
+                
+                SettingsInfoCard(
+                    text = "Manueller Sync exportiert alle Notizen als .md-Dateien und " +
+                        "importiert .md-Dateien vom Server. Nützlich für einmalige Synchronisation."
+                )
+                
+                Spacer(modifier = Modifier.height(8.dp))
+                
+                SettingsButton(
+                    text = "📝 Manueller Markdown-Sync",
+                    onClick = { viewModel.performManualMarkdownSync() },
+                    modifier = Modifier.padding(horizontal = 16.dp)
+                )
+            }
+            
+            Spacer(modifier = Modifier.height(16.dp))
+        }
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/screens/ServerSettingsScreen.kt

@@ -0,0 +1,241 @@
+package dev.dettmer.simplenotes.ui.settings.screens
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Language
+import androidx.compose.material.icons.filled.Lock
+import androidx.compose.material.icons.filled.Person
+import androidx.compose.material.icons.filled.Visibility
+import androidx.compose.material.icons.filled.VisibilityOff
+import androidx.compose.material3.Button
+import androidx.compose.material3.Card
+import androidx.compose.material3.CardDefaults
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.FilterChip
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.text.input.PasswordVisualTransformation
+import androidx.compose.ui.text.input.VisualTransformation
+import androidx.compose.ui.unit.dp
+import dev.dettmer.simplenotes.ui.settings.SettingsViewModel
+import dev.dettmer.simplenotes.ui.settings.components.SettingsScaffold
+
+/**
+ * Server configuration settings screen
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun ServerSettingsScreen(
+    viewModel: SettingsViewModel,
+    onBack: () -> Unit
+) {
+    val serverUrl by viewModel.serverUrl.collectAsState()
+    val username by viewModel.username.collectAsState()
+    val password by viewModel.password.collectAsState()
+    val isHttps by viewModel.isHttps.collectAsState()
+    val serverStatus by viewModel.serverStatus.collectAsState()
+    val isSyncing by viewModel.isSyncing.collectAsState()
+    
+    var passwordVisible by remember { mutableStateOf(false) }
+    
+    // Check server status on load
+    LaunchedEffect(Unit) {
+        viewModel.checkServerStatus()
+    }
+    
+    SettingsScaffold(
+        title = "Server-Einstellungen",
+        onBack = onBack
+    ) { paddingValues ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues)
+                .verticalScroll(rememberScrollState())
+                .padding(16.dp)
+        ) {
+            // Verbindungstyp
+            Text(
+                text = "Verbindungstyp",
+                style = MaterialTheme.typography.labelLarge,
+                modifier = Modifier.padding(bottom = 8.dp)
+            )
+            
+            Row(
+                modifier = Modifier.fillMaxWidth(),
+                horizontalArrangement = Arrangement.spacedBy(8.dp)
+            ) {
+                FilterChip(
+                    selected = !isHttps,
+                    onClick = { viewModel.updateProtocol(false) },
+                    label = { Text("🏠 Intern (HTTP)") },
+                    modifier = Modifier.weight(1f)
+                )
+                FilterChip(
+                    selected = isHttps,
+                    onClick = { viewModel.updateProtocol(true) },
+                    label = { Text("🌐 Extern (HTTPS)") },
+                    modifier = Modifier.weight(1f)
+                )
+            }
+            
+            Text(
+                text = if (!isHttps) {
+                    "HTTP nur für lokale Netzwerke (z.B. 192.168.x.x, 10.x.x.x)"
+                } else {
+                    "HTTPS für sichere Verbindungen über das Internet"
+                },
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                modifier = Modifier.padding(top = 4.dp, bottom = 16.dp)
+            )
+            
+            // Server-Adresse
+            OutlinedTextField(
+                value = serverUrl,
+                onValueChange = { viewModel.updateServerUrl(it) },
+                label = { Text("Server-Adresse") },
+                supportingText = { Text("z.B. http://192.168.0.188:8080/notes") },
+                leadingIcon = { Icon(Icons.Default.Language, null) },
+                modifier = Modifier.fillMaxWidth(),
+                singleLine = true,
+                keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Uri)
+            )
+            
+            Spacer(modifier = Modifier.height(12.dp))
+            
+            // Benutzername
+            OutlinedTextField(
+                value = username,
+                onValueChange = { viewModel.updateUsername(it) },
+                label = { Text("Benutzername") },
+                leadingIcon = { Icon(Icons.Default.Person, null) },
+                modifier = Modifier.fillMaxWidth(),
+                singleLine = true
+            )
+            
+            Spacer(modifier = Modifier.height(12.dp))
+            
+            // Passwort
+            OutlinedTextField(
+                value = password,
+                onValueChange = { viewModel.updatePassword(it) },
+                label = { Text("Passwort") },
+                leadingIcon = { Icon(Icons.Default.Lock, null) },
+                trailingIcon = {
+                    IconButton(onClick = { passwordVisible = !passwordVisible }) {
+                        Icon(
+                            imageVector = if (passwordVisible) {
+                                Icons.Default.VisibilityOff
+                            } else {
+                                Icons.Default.Visibility
+                            },
+                            contentDescription = if (passwordVisible) "Verstecken" else "Anzeigen"
+                        )
+                    }
+                },
+                visualTransformation = if (passwordVisible) {
+                    VisualTransformation.None
+                } else {
+                    PasswordVisualTransformation()
+                },
+                modifier = Modifier.fillMaxWidth(),
+                singleLine = true,
+                keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password)
+            )
+            
+            Spacer(modifier = Modifier.height(16.dp))
+            
+            // Server-Status
+            Card(
+                modifier = Modifier.fillMaxWidth(),
+                colors = CardDefaults.cardColors(
+                    containerColor = MaterialTheme.colorScheme.surfaceContainerHighest
+                )
+            ) {
+                Row(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .padding(16.dp),
+                    horizontalArrangement = Arrangement.SpaceBetween,
+                    verticalAlignment = Alignment.CenterVertically
+                ) {
+                    Text("Server-Status:", style = MaterialTheme.typography.labelLarge)
+                    Text(
+                        text = when (serverStatus) {
+                            is SettingsViewModel.ServerStatus.Reachable -> "✅ Erreichbar"
+                            is SettingsViewModel.ServerStatus.Unreachable -> "❌ Nicht erreichbar"
+                            is SettingsViewModel.ServerStatus.Checking -> "🔍 Prüfe..."
+                            is SettingsViewModel.ServerStatus.NotConfigured -> "⚠️ Nicht konfiguriert"
+                            else -> "❓ Unbekannt"
+                        },
+                        color = when (serverStatus) {
+                            is SettingsViewModel.ServerStatus.Reachable -> Color(0xFF4CAF50)
+                            is SettingsViewModel.ServerStatus.Unreachable -> Color(0xFFF44336)
+                            is SettingsViewModel.ServerStatus.NotConfigured -> Color(0xFFFF9800)
+                            else -> MaterialTheme.colorScheme.onSurfaceVariant
+                        }
+                    )
+                }
+            }
+            
+            Spacer(modifier = Modifier.height(24.dp))
+            
+            // Action Buttons
+            Row(
+                modifier = Modifier.fillMaxWidth(),
+                horizontalArrangement = Arrangement.spacedBy(8.dp)
+            ) {
+                OutlinedButton(
+                    onClick = { viewModel.testConnection() },
+                    modifier = Modifier.weight(1f)
+                ) {
+                    Text("Verbindung testen")
+                }
+                
+                Button(
+                    onClick = { viewModel.syncNow() },
+                    enabled = !isSyncing,
+                    modifier = Modifier.weight(1f)
+                ) {
+                    if (isSyncing) {
+                        CircularProgressIndicator(
+                            modifier = Modifier.size(16.dp),
+                            strokeWidth = 2.dp,
+                            color = MaterialTheme.colorScheme.onPrimary
+                        )
+                        Spacer(modifier = Modifier.width(8.dp))
+                    }
+                    Text("Jetzt synchronisieren")
+                }
+            }
+        }
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/screens/SettingsMainScreen.kt

@@ -0,0 +1,143 @@
+package dev.dettmer.simplenotes.ui.settings.screens
+
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Backup
+import androidx.compose.material.icons.filled.BugReport
+import androidx.compose.material.icons.filled.Cloud
+import androidx.compose.material.icons.filled.Description
+import androidx.compose.material.icons.filled.Info
+import androidx.compose.material.icons.filled.Sync
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.unit.dp
+import dev.dettmer.simplenotes.BuildConfig
+import dev.dettmer.simplenotes.ui.settings.SettingsRoute
+import dev.dettmer.simplenotes.ui.settings.SettingsViewModel
+import dev.dettmer.simplenotes.ui.settings.components.SettingsCard
+import dev.dettmer.simplenotes.ui.settings.components.SettingsScaffold
+
+/**
+ * Main Settings overview screen with clickable group cards
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun SettingsMainScreen(
+    viewModel: SettingsViewModel,
+    onNavigate: (SettingsRoute) -> Unit,
+    onBack: () -> Unit
+) {
+    val serverUrl by viewModel.serverUrl.collectAsState()
+    val serverStatus by viewModel.serverStatus.collectAsState()
+    val autoSyncEnabled by viewModel.autoSyncEnabled.collectAsState()
+    val syncInterval by viewModel.syncInterval.collectAsState()
+    val markdownAutoSync by viewModel.markdownAutoSync.collectAsState()
+    val fileLoggingEnabled by viewModel.fileLoggingEnabled.collectAsState()
+    
+    // Check server status on first load
+    LaunchedEffect(Unit) {
+        viewModel.checkServerStatus()
+    }
+    
+    SettingsScaffold(
+        title = "Einstellungen",
+        onBack = onBack
+    ) { paddingValues ->
+        LazyColumn(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues),
+            contentPadding = PaddingValues(vertical = 8.dp)
+        ) {
+            // Server-Einstellungen
+            item {
+                // v1.5.0 Fix: Nur Prefix-URLs gelten als "nicht konfiguriert"
+                val isConfigured = serverUrl.isNotEmpty() && 
+                    serverUrl != "http://" && 
+                    serverUrl != "https://"
+                
+                SettingsCard(
+                    icon = Icons.Default.Cloud,
+                    title = "Server-Einstellungen",
+                    subtitle = if (isConfigured) serverUrl else null,
+                    statusText = when (serverStatus) {
+                        is SettingsViewModel.ServerStatus.Reachable -> "✅ Erreichbar"
+                        is SettingsViewModel.ServerStatus.Unreachable -> "❌ Nicht erreichbar"
+                        is SettingsViewModel.ServerStatus.Checking -> "🔍 Prüfe..."
+                        is SettingsViewModel.ServerStatus.NotConfigured -> "⚠️ Nicht konfiguriert"
+                        else -> null
+                    },
+                    statusColor = when (serverStatus) {
+                        is SettingsViewModel.ServerStatus.Reachable -> Color(0xFF4CAF50)
+                        is SettingsViewModel.ServerStatus.Unreachable -> Color(0xFFF44336)
+                        is SettingsViewModel.ServerStatus.NotConfigured -> Color(0xFFFF9800)
+                        else -> Color.Gray
+                    },
+                    onClick = { onNavigate(SettingsRoute.Server) }
+                )
+            }
+            
+            // Sync-Einstellungen
+            item {
+                val intervalText = when (syncInterval) {
+                    15L -> "15 Min"
+                    60L -> "60 Min"
+                    else -> "30 Min"
+                }
+                SettingsCard(
+                    icon = Icons.Default.Sync,
+                    title = "Sync-Einstellungen",
+                    subtitle = if (autoSyncEnabled) "Auto-Sync: An • $intervalText" else "Auto-Sync: Aus",
+                    onClick = { onNavigate(SettingsRoute.Sync) }
+                )
+            }
+            
+            // Markdown-Integration
+            item {
+                SettingsCard(
+                    icon = Icons.Default.Description,
+                    title = "Markdown Desktop-Integration",
+                    subtitle = if (markdownAutoSync) "Auto-Sync: An" else "Auto-Sync: Aus",
+                    onClick = { onNavigate(SettingsRoute.Markdown) }
+                )
+            }
+            
+            // Backup & Wiederherstellung
+            item {
+                SettingsCard(
+                    icon = Icons.Default.Backup,
+                    title = "Backup & Wiederherstellung",
+                    subtitle = "Lokales oder Server-Backup",
+                    onClick = { onNavigate(SettingsRoute.Backup) }
+                )
+            }
+            
+            // Über diese App
+            item {
+                SettingsCard(
+                    icon = Icons.Default.Info,
+                    title = "Über diese App",
+                    subtitle = "Version ${BuildConfig.VERSION_NAME}",
+                    onClick = { onNavigate(SettingsRoute.About) }
+                )
+            }
+            
+            // Debug & Diagnose
+            item {
+                SettingsCard(
+                    icon = Icons.Default.BugReport,
+                    title = "Debug & Diagnose",
+                    subtitle = if (fileLoggingEnabled) "Logging: An" else "Logging: Aus",
+                    onClick = { onNavigate(SettingsRoute.Debug) }
+                )
+            }
+        }
+    }
+}

android/app/src/main/java/dev/dettmer/simplenotes/ui/settings/screens/SyncSettingsScreen.kt

@@ -0,0 +1,112 @@
+package dev.dettmer.simplenotes.ui.settings.screens
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Sync
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import dev.dettmer.simplenotes.ui.settings.SettingsViewModel
+import dev.dettmer.simplenotes.ui.settings.components.RadioOption
+import dev.dettmer.simplenotes.ui.settings.components.SettingsDivider
+import dev.dettmer.simplenotes.ui.settings.components.SettingsInfoCard
+import dev.dettmer.simplenotes.ui.settings.components.SettingsRadioGroup
+import dev.dettmer.simplenotes.ui.settings.components.SettingsScaffold
+import dev.dettmer.simplenotes.ui.settings.components.SettingsSectionHeader
+import dev.dettmer.simplenotes.ui.settings.components.SettingsSwitch
+
+/**
+ * Sync settings screen (Auto-Sync toggle and interval selection)
+ * v1.5.0: Jetpack Compose Settings Redesign
+ */
+@Composable
+fun SyncSettingsScreen(
+    viewModel: SettingsViewModel,
+    onBack: () -> Unit
+) {
+    val autoSyncEnabled by viewModel.autoSyncEnabled.collectAsState()
+    val syncInterval by viewModel.syncInterval.collectAsState()
+    
+    SettingsScaffold(
+        title = "Sync-Einstellungen",
+        onBack = onBack
+    ) { paddingValues ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(paddingValues)
+                .verticalScroll(rememberScrollState())
+        ) {
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // Auto-Sync Info
+            SettingsInfoCard(
+                text = "🔄 Auto-Sync:\n" +
+                    "• Prüft alle 30 Min. ob Server erreichbar\n" +
+                    "• Funktioniert bei jeder WiFi-Verbindung\n" +
+                    "• Läuft auch im Hintergrund\n" +
+                    "• Minimaler Akkuverbrauch (~0.4%/Tag)"
+            )
+            
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // Auto-Sync Toggle
+            SettingsSwitch(
+                title = "Auto-Sync aktiviert",
+                checked = autoSyncEnabled,
+                onCheckedChange = { viewModel.setAutoSync(it) },
+                icon = Icons.Default.Sync
+            )
+            
+            SettingsDivider()
+            
+            // Sync Interval Section
+            SettingsSectionHeader(text = "Sync-Intervall")
+            
+            SettingsInfoCard(
+                text = "Legt fest, wie oft die App im Hintergrund synchronisiert. " +
+                    "Kürzere Intervalle bedeuten aktuellere Daten, verbrauchen aber etwas mehr Akku.\n\n" +
+                    "⏱️ Hinweis: Wenn dein Smartphone im Standby ist, kann Android die " +
+                    "Synchronisation verzögern (bis zu 60 Min.), um Akku zu sparen. " +
+                    "Das ist normal und betrifft alle Hintergrund-Apps."
+            )
+            
+            Spacer(modifier = Modifier.height(8.dp))
+            
+            // Interval Radio Group
+            val intervalOptions = listOf(
+                RadioOption(
+                    value = 15L,
+                    title = "⚡ Alle 15 Minuten",
+                    subtitle = "Schnellste Synchronisation • ~0.8% Akku/Tag (~23 mAh)"
+                ),
+                RadioOption(
+                    value = 30L,
+                    title = "✓ Alle 30 Minuten (Empfohlen)",
+                    subtitle = "Ausgewogenes Verhältnis • ~0.4% Akku/Tag (~12 mAh)"
+                ),
+                RadioOption(
+                    value = 60L,
+                    title = "🔋 Alle 60 Minuten",
+                    subtitle = "Maximale Akkulaufzeit • ~0.2% Akku/Tag (~6 mAh geschätzt)"
+                )
+            )
+            
+            SettingsRadioGroup(
+                options = intervalOptions,
+                selectedValue = syncInterval,
+                onValueSelected = { viewModel.setSyncInterval(it) }
+            )
+            
+            Spacer(modifier = Modifier.height(16.dp))
+        }
+    }
+}