diff --git a/phone_app/lib/screens/github_mirror_screen.dart b/phone_app/lib/screens/github_mirror_screen.dart
new file mode 100644
index 0000000..54f5583
--- /dev/null
+++ b/phone_app/lib/screens/github_mirror_screen.dart
@@ -0,0 +1,240 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:url_launcher/url_launcher.dart';
+
+import 'package:wake_alarm_sync/services/github_device_auth.dart';
+import 'package:wake_alarm_sync/services/sync_settings.dart';
+
+/// The GitHub mirror screen: cutover-only sync transport, not a peer of
+/// Firebase.
+///
+/// Kept app-local rather than folded into the shared `sync_settings_ui`
+/// package since that package carries no GitHub surface at all. Logic moved
+/// verbatim from the old combined settings screen.
+class GitHubMirrorScreen extends StatefulWidget {
+  /// Creates a [GitHubMirrorScreen].
+  const GitHubMirrorScreen({super.key});
+
+  @override
+  State<GitHubMirrorScreen> createState() => _GitHubMirrorScreenState();
+}
+
+class _GitHubMirrorScreenState extends State<GitHubMirrorScreen> {
+  SyncSettings _settings = const SyncSettings(token: '');
+  bool _busy = false;
+  String _status = '';
+
+  @override
+  void initState() {
+    super.initState();
+    unawaited(_load());
+  }
+
+  Future<void> _load() async {
+    final s = await SyncSettings.load();
+    if (!mounted) return;
+    setState(() => _settings = s);
+  }
+
+  Future<void> _connectGitHub() async {
+    final auth = GitHubDeviceAuth(clientId: SyncSettings.defaultClientId);
+    try {
+      final device = await auth.requestDeviceCode();
+      if (!mounted) return;
+      final token = await showDialog<String>(
+        context: context,
+        barrierDismissible: false,
+        builder: (_) => _DeviceCodeDialog(device: device, auth: auth),
+      );
+      if (token == null || token.isEmpty) return;
+
+      setState(() {
+        _busy = true;
+        _status = 'Connecting…';
+      });
+      final updated = SyncSettings(token: token);
+      await updated.save();
+      if (mounted) {
+        setState(() {
+          _settings = updated;
+          _busy = false;
+          _status = 'Connected! Alarm will sync to kuhyx/syncs.';
+        });
+      }
+    } on Exception catch (e) {
+      if (mounted) {
+        setState(() {
+          _busy = false;
+          _status = 'Error: $e';
+        });
+      }
+    } finally {
+      auth.close();
+    }
+  }
+
+  Future<void> _disconnect() async {
+    await SyncSettings.clear();
+    if (mounted) {
+      setState(() {
+        _settings = const SyncSettings(token: '');
+        _status = 'Disconnected.';
+      });
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final isConnected = _settings.isConfigured;
+    return Scaffold(
+      appBar: AppBar(title: const Text('Advanced sync (GitHub)')),
+      body: SafeArea(
+        child: SingleChildScrollView(
+          padding: const EdgeInsets.all(16),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            children: [
+              Align(
+                alignment: Alignment.centerLeft,
+                child: Text(
+                  isConnected
+                      ? 'Connected to GitHub.'
+                      : 'Not connected to GitHub.',
+                  style: TextStyle(
+                    fontSize: 16,
+                    color: Theme.of(context).colorScheme.onSurfaceVariant,
+                  ),
+                ),
+              ),
+              const SizedBox(height: 12),
+              if (!isConnected)
+                ElevatedButton.icon(
+                  onPressed: _busy ? null : _connectGitHub,
+                  icon: const Icon(Icons.link),
+                  label: const Text('Connect GitHub'),
+                )
+              else
+                OutlinedButton.icon(
+                  onPressed: _busy ? null : _disconnect,
+                  icon: const Icon(Icons.link_off),
+                  label: const Text('Disconnect GitHub'),
+                ),
+              const SizedBox(height: 16),
+              Text(
+                'PC config — the PC reads Firebase first and falls back '
+                'to GitHub. For the GitHub fallback, create:\n'
+                '~/.config/wake_alarm/sync.json\n\n'
+                '{ "token": "<same token>" }\n\n'
+                'The token needs "repo" scope so the PC can read '
+                'kuhyx/syncs.',
+                style: TextStyle(
+                  fontSize: 16,
+                  color: Theme.of(context).colorScheme.onSurfaceVariant,
+                ),
+              ),
+              if (_status.isNotEmpty) ...[
+                const SizedBox(height: 16),
+                Text(
+                  _status,
+                  style: TextStyle(
+                    color: _status.startsWith('Error')
+                        ? Theme.of(context).colorScheme.error
+                        : null,
+                  ),
+                ),
+              ],
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+/// Dialog shown while waiting for the user to authorize on GitHub.
+class _DeviceCodeDialog extends StatefulWidget {
+  const _DeviceCodeDialog({required this.device, required this.auth});
+
+  final DeviceCodeResponse device;
+  final GitHubDeviceAuth auth;
+
+  @override
+  State<_DeviceCodeDialog> createState() => _DeviceCodeDialogState();
+}
+
+class _DeviceCodeDialogState extends State<_DeviceCodeDialog> {
+  String? _error;
+
+  @override
+  void initState() {
+    super.initState();
+    unawaited(_poll());
+  }
+
+  Future<void> _poll() async {
+    try {
+      final token = await widget.auth.pollForToken(widget.device);
+      if (mounted) Navigator.of(context).pop(token);
+    } on Exception catch (e) {
+      if (mounted) setState(() => _error = '$e');
+    }
+  }
+
+  Future<void> _openPage() async {
+    await Clipboard.setData(ClipboardData(text: widget.device.userCode));
+    await launchUrl(
+      Uri.parse(widget.device.verificationUri),
+      mode: LaunchMode.externalApplication,
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      title: const Text('Authorize on GitHub'),
+      content: Column(
+        mainAxisSize: MainAxisSize.min,
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          const Text('Enter this code on GitHub:'),
+          const SizedBox(height: 8),
+          SelectableText(
+            widget.device.userCode,
+            style: Theme.of(context).textTheme.headlineSmall,
+          ),
+          const SizedBox(height: 16),
+          if (_error == null)
+            const Row(
+              children: [
+                SizedBox(
+                  width: 16,
+                  height: 16,
+                  child: CircularProgressIndicator(strokeWidth: 2),
+                ),
+                SizedBox(width: 12),
+                Expanded(child: Text('Waiting for authorization…')),
+              ],
+            )
+          else
+            Text(
+              _error!,
+              style: TextStyle(color: Theme.of(context).colorScheme.error),
+            ),
+        ],
+      ),
+      actions: [
+        TextButton(
+          onPressed: () => Navigator.of(context).pop(),
+          child: const Text('Cancel'),
+        ),
+        FilledButton.icon(
+          onPressed: _openPage,
+          icon: const Icon(Icons.open_in_new),
+          label: const Text('Open GitHub & copy code'),
+        ),
+      ],
+    );
+  }
+}
diff --git a/phone_app/lib/screens/settings_screen.dart b/phone_app/lib/screens/settings_screen.dart
index 9da395b..627f9bf 100644
--- a/phone_app/lib/screens/settings_screen.dart
+++ b/phone_app/lib/screens/settings_screen.dart
@@ -1,527 +1,56 @@
-import 'dart:async';
-
-import 'package:crdt_sync/crdt_sync.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter/services.dart';
-import 'package:url_launcher/url_launcher.dart';
+import 'package:sync_settings_ui/sync_settings_ui.dart';
 
+import 'package:wake_alarm_sync/screens/github_mirror_screen.dart';
 import 'package:wake_alarm_sync/services/firebase_backend.dart';
-import 'package:wake_alarm_sync/services/github_device_auth.dart';
 import 'package:wake_alarm_sync/services/google_sign_in_backend.dart';
-import 'package:wake_alarm_sync/services/sync_settings.dart';
-import 'package:wake_alarm_sync/ui/theme.dart';
 
-/// Settings screen for the backends the alarm syncs through.
+/// Settings screen: links to the two sync surfaces.
 ///
-/// Firebase is the primary path: sign in once with the shared sync account,
-/// whose password is kept in the OS keystore. GitHub is only the cutover
-/// mirror, so its device-flow connection sits under "Advanced" rather than
-/// competing with Firebase as a visible choice.
-class SettingsScreen extends StatefulWidget {
+/// "Sync settings" is the shared `sync_settings_ui` package (Firebase,
+/// identical in shape to every other kuhy app's Sync settings screen).
+/// "Advanced sync (GitHub)" stays app-local ([GitHubMirrorScreen]).
+class SettingsScreen extends StatelessWidget {
   /// Creates a [SettingsScreen].
-  const SettingsScreen({
-    super.key,
-    this.googleFirebaseFactory,
-    this.googleAvailable,
-    this.accountLoader,
-    this.sessionProbe,
-  });
-
-  /// Builds the Firebase backend via Google sign-in. Injected so tests need
-  /// no platform channel -- the plugin reaches the OS account picker.
-  final Future<FirebaseRestClient?> Function()? googleFirebaseFactory;
-
-  /// Whether to offer the Google button. Defaults to what the platform
-  /// supports; injected by tests, whose host reports unsupported.
-  final bool? googleAvailable;
-
-  /// Reads the stored Firebase account. Injected for the same reason as
-  /// [googleFirebaseFactory]: the keystore is a platform channel.
-  final Future<FirebaseAccount?> Function()? accountLoader;
-
-  /// Whether a Firebase session is stored. See [accountLoader].
-  ///
-  /// Separate from [accountLoader] because the two answer different
-  /// questions: the account marker is bookkeeping, the session is the
-  /// credential. A device can hold the second without the first, and
-  /// reporting only the first is what made a syncing phone read as
-  /// "not connected".
-  final Future<bool> Function()? sessionProbe;
-
-  @override
-  State<SettingsScreen> createState() => _SettingsScreenState();
-}
-
-class _SettingsScreenState extends State<SettingsScreen> {
-  SyncSettings _settings = const SyncSettings(token: '');
-  final _emailController = TextEditingController();
-  final _passwordController = TextEditingController();
-  bool _firebaseConnected = false;
-  bool _busy = false;
-  String _status = '';
-
-  @override
-  void initState() {
-    super.initState();
-    unawaited(_load());
-  }
-
-  @override
-  void dispose() {
-    _emailController.dispose();
-    _passwordController.dispose();
-    super.dispose();
-  }
-
-  Future<void> _load() async {
-    final s = await SyncSettings.load();
-    // Reflect a previously-stored account, so a returning user sees the real
-    // state instead of an empty form that looks unconfigured.
-    final account = await loadAccount();
-    // The stored session, not the account marker, decides "connected": a
-    // Google sign-in leaves a refresh token that authenticates every request
-    // even when no marker was written beside it.
-    final connected = await (widget.sessionProbe ?? isFirebaseConfigured)();
-    if (!mounted) return;
-    if (account != null) _emailController.text = account.email;
-    setState(() {
-      _settings = s;
-      _firebaseConnected = connected;
-    });
-  }
-
-  /// Stores the typed account and signs in immediately, so a typo surfaces
-  /// here rather than as a silent background failure at push time.
-
-  /// Signs in by picking a Google account -- the one-tap path.
-  ///
-  /// A dismissed picker is not an error; a wrong-account sign-in reports why,
-  /// because that is the failure that otherwise looks like a working sync
-  /// which silently never syncs.
-  Future<void> _connectGoogle() async {
-    setState(() {
-      _busy = true;
-      _status = 'Signing in...';
-    });
-    try {
-      final client =
-          await (widget.googleFirebaseFactory ?? openFirebaseWithGoogle)();
-      if (!mounted) return;
-      if (client == null) {
-        setState(() {
-          _busy = false;
-          _status = 'Google sign-in was cancelled.';
-        });
-        return;
-      }
-      // openFirebaseWithGoogle stored the account under the email Firebase
-      // reported; reflect it rather than reading the (empty) form field.
-      final account = await (widget.accountLoader ?? storedAccount)();
-      // Report the persisted state, not the fact that the call returned a
-      // client: a non-null client only means sign-in succeeded in that
-      // moment, which is how four apps claimed "Connected" and then synced
-      // over GitHub after the next restart.
-      final connected = await (widget.sessionProbe ?? isFirebaseConfigured)();
-      if (!mounted) return;
-      if (account != null) _emailController.text = account.email;
-      setState(() {
-        _busy = false;
-        _firebaseConnected = connected;
-        _status = connected
-            ? 'Connected to Firebase.'
-            : 'Signed in, but this device did not save the session - it will '
-                  'sync over GitHub after a restart. Try connecting again.';
-      });
-    } on FirebaseAuthError catch (error) {
-      if (!mounted) return;
-      setState(() {
-        _busy = false;
-        _firebaseConnected = false;
-        _status = error.message;
-      });
-    } on Object catch (error) {
-      // Broader than Exception on purpose: a missing platform binding raises
-      // an Error, and anything escaping here leaves the button disabled and
-      // the screen stuck on "Signing in..." forever -- which is exactly what
-      // happened on the phone before storedAccount() replaced loadAccount().
-      if (!mounted) return;
-      setState(() {
-        _busy = false;
-        _firebaseConnected = false;
-        _status = 'Google sign-in failed: $error';
-      });
-    }
-  }
-
-  Future<void> _connectFirebase() async {
-    final email = _emailController.text.trim();
-    final password = _passwordController.text;
-    if (email.isEmpty || password.isEmpty) {
-      setState(() => _status = 'Enter the sync account email and password.');
-      return;
-    }
-    setState(() {
-      _busy = true;
-      _status = 'Signing in…';
-    });
-    await saveAccount(FirebaseAccount(email: email, password: password));
-    final client = await openFirebase();
-    if (!mounted) return;
-    if (client == null) {
-      await clearAccount();
-      setState(() {
-        _busy = false;
-        _firebaseConnected = false;
-        _status = 'Error: Firebase rejected that account.';
-      });
-      return;
-    }
-    _passwordController.clear();
-    setState(() {
-      _busy = false;
-      _firebaseConnected = true;
-      _status = 'Connected to Firebase.';
-    });
-  }
-
-  Future<void> _disconnectFirebase() async {
-    await clearAccount();
-    if (!mounted) return;
-    _emailController.clear();
-    _passwordController.clear();
-    setState(() {
-      _firebaseConnected = false;
-      _status = 'Firebase disconnected.';
-    });
-  }
-
-  Future<void> _connectGitHub() async {
-    final auth = GitHubDeviceAuth(clientId: SyncSettings.defaultClientId);
-    try {
-      final device = await auth.requestDeviceCode();
-      if (!mounted) return;
-      final token = await showDialog<String>(
-        context: context,
-        barrierDismissible: false,
-        builder: (_) => _DeviceCodeDialog(device: device, auth: auth),
-      );
-      if (token == null || token.isEmpty) return;
-
-      setState(() {
-        _busy = true;
-        _status = 'Connecting…';
-      });
-      final updated = SyncSettings(token: token);
-      await updated.save();
-      if (mounted) {
-        setState(() {
-          _settings = updated;
-          _busy = false;
-          _status = 'Connected! Alarm will sync to kuhyx/syncs.';
-        });
-      }
-    } on Exception catch (e) {
-      if (mounted) {
-        setState(() {
-          _busy = false;
-          _status = 'Error: $e';
-        });
-      }
-    } finally {
-      auth.close();
-    }
-  }
-
-  Future<void> _disconnect() async {
-    await SyncSettings.clear();
-    if (mounted) {
-      setState(() {
-        _settings = const SyncSettings(token: '');
-        _status = 'Disconnected.';
-      });
-    }
-  }
+  const SettingsScreen({super.key});
 
   @override
   Widget build(BuildContext context) {
-    final isConnected = _settings.isConfigured;
     return Scaffold(
       appBar: AppBar(title: const Text('Settings')),
-      // Scrollable: this screen carries a five-line explanatory paragraph and
-      // an unbounded `'Error: \$e'`, inside a Column that could not scroll.
-      body: SafeArea(
-        child: SingleChildScrollView(
-          padding: const EdgeInsets.all(16),
-          child: Column(
-            crossAxisAlignment: CrossAxisAlignment.stretch,
-            children: [
-              _StatusCard(connected: _firebaseConnected),
-              const SizedBox(height: 16),
-              Text(
-                'Firebase sync',
-                style: Theme.of(context).textTheme.titleMedium,
-              ),
-              const SizedBox(height: 8),
-              Text(
-                _firebaseConnected
-                    ? 'Connected. The alarm goes to Firebase first, and still '
-                          'mirrors to GitHub until every device has moved.'
-                    : 'Not connected — syncing over GitHub only. Enter the '
-                          'shared sync account to move this device over. The '
-                          'password is kept in the device keystore, never in '
-                          'the app or the repo.',
-                style: TextStyle(
-                  fontSize: 16,
-                  color: Theme.of(context).colorScheme.onSurfaceVariant,
-                ),
-              ),
-              const SizedBox(height: 12),
-              // Once connected the account is shown as read-only text: an
-              // editable email box beside an empty password box reads as
-              // "you still have to enter this", making a connected device
-              // look unconfigured.
-              if (_firebaseConnected)
-                Row(
-                  children: [
-                    const Icon(Icons.cloud_done, size: 20),
-                    const SizedBox(width: 8),
-                    Expanded(child: Text(_emailController.text)),
-                    TextButton(
-                      onPressed: _busy ? null : _disconnectFirebase,
-                      child: const Text('Disconnect'),
-                    ),
-                  ],
-                )
-              else ...[
-                TextField(
-                  controller: _emailController,
-                  keyboardType: TextInputType.emailAddress,
-                  autocorrect: false,
-                  decoration: const InputDecoration(
-                    labelText: 'Sync account email',
-                  ),
-                ),
-                const SizedBox(height: 8),
-                TextField(
-                  controller: _passwordController,
-                  obscureText: true,
-                  autocorrect: false,
-                  decoration: const InputDecoration(
-                    labelText: 'Sync account password',
-                  ),
-                ),
-                const SizedBox(height: 12),
-                FilledButton.icon(
-                  onPressed: _busy ? null : _connectFirebase,
-                  icon: _busy
-                      ? const SizedBox(
-                          width: 18,
-                          height: 18,
-                          child: CircularProgressIndicator(strokeWidth: 2),
-                        )
-                      : const Icon(Icons.cloud_done),
-                  label: const Text('Connect Firebase'),
-                ),
-                // One tap, no typing -- the path that matters after a
-                // reinstall. Hidden where the platform has no programmatic
-                // Google flow (see google_platform.dart); a button that
-                // always failed would be worse than none.
-                if (widget.googleAvailable ?? googleSignInSupported) ...[
-                  const SizedBox(height: 12),
-                  FilledButton.icon(
-                    onPressed: _busy ? null : _connectGoogle,
-                    icon: const Icon(Icons.account_circle),
-                    label: const Text('Sign in with Google'),
-                  ),
-                ],
-              ],
-              const SizedBox(height: 16),
-              if (_status.isNotEmpty)
-                Text(
-                  _status,
-                  style: TextStyle(
-                    color: _status.contains('Error')
-                        ? Theme.of(context).colorScheme.error
-                        : Theme.of(
-                            context,
-                          ).extension<AppStatusColors>()!.success,
-                  ),
-                ),
-              const Divider(height: 32),
-              // GitHub is the cutover mirror, not a choice: everything about
-              // it lives here so the primary path stays a single decision.
-              ExpansionTile(
-                title: const Text('Advanced (GitHub mirror)'),
-                tilePadding: EdgeInsets.zero,
-                childrenPadding: const EdgeInsets.only(bottom: 8),
-                children: [
-                  Align(
-                    alignment: Alignment.centerLeft,
-                    child: Text(
-                      isConnected
-                          ? 'Connected to GitHub.'
-                          : 'Not connected to GitHub.',
-                      style: TextStyle(
-                        fontSize: 16,
-                        color: Theme.of(context).colorScheme.onSurfaceVariant,
-                      ),
-                    ),
-                  ),
-                  const SizedBox(height: 12),
-                  if (!isConnected)
-                    ElevatedButton.icon(
-                      onPressed: _busy ? null : _connectGitHub,
-                      icon: const Icon(Icons.link),
-                      label: const Text('Connect GitHub'),
-                    )
-                  else
-                    OutlinedButton.icon(
-                      onPressed: _busy ? null : _disconnect,
-                      icon: const Icon(Icons.link_off),
-                      label: const Text('Disconnect GitHub'),
-                    ),
-                  const SizedBox(height: 16),
-                  Text(
-                    'PC config — the PC reads Firebase first and falls back '
-                    'to GitHub. For the GitHub fallback, create:\n'
-                    '~/.config/wake_alarm/sync.json\n\n'
-                    '{ "token": "<same token>" }\n\n'
-                    'The token needs "repo" scope so the PC can read '
-                    'kuhyx/syncs.',
-                    // Was 12px/Colors.grey — below the 16px reading floor
-                    // (rule 20) and off-palette (rule 4); this is real setup
-                    // instructions, not decorative chrome.
-                    style: TextStyle(
-                      fontSize: 16,
-                      color: Theme.of(context).colorScheme.onSurfaceVariant,
-                    ),
-                  ),
-                ],
-              ),
-            ],
-          ),
-        ),
-      ),
-    );
-  }
-}
-
-class _StatusCard extends StatelessWidget {
-  const _StatusCard({required this.connected});
-
-  final bool connected;
-
-  @override
-  Widget build(BuildContext context) {
-    final colorScheme = Theme.of(context).colorScheme;
-    final success = Theme.of(context).extension<AppStatusColors>()!.success;
-    return Card(
-      child: Padding(
+      body: ListView(
         padding: const EdgeInsets.all(16),
-        child: Row(
-          children: [
-            Icon(
-              connected ? Icons.check_circle : Icons.cancel,
-              // Dimmed relative to the adjacent label text (rule 28).
-              color: (connected ? success : colorScheme.error).withValues(
-                alpha: 0.8,
-              ),
-            ),
-            const SizedBox(width: 8),
-            Expanded(
-              child: Text(
-                connected ? 'Connected to Firebase' : 'Not connected',
-              ),
-            ),
-          ],
-        ),
-      ),
-    );
-  }
-}
-
-/// Dialog shown while waiting for the user to authorize on GitHub.
-class _DeviceCodeDialog extends StatefulWidget {
-  const _DeviceCodeDialog({required this.device, required this.auth});
-
-  final DeviceCodeResponse device;
-  final GitHubDeviceAuth auth;
-
-  @override
-  State<_DeviceCodeDialog> createState() => _DeviceCodeDialogState();
-}
-
-class _DeviceCodeDialogState extends State<_DeviceCodeDialog> {
-  String? _error;
-
-  @override
-  void initState() {
-    super.initState();
-    unawaited(_poll());
-  }
-
-  Future<void> _poll() async {
-    try {
-      final token = await widget.auth.pollForToken(widget.device);
-      if (mounted) Navigator.of(context).pop(token);
-    } on Exception catch (e) {
-      if (mounted) setState(() => _error = '$e');
-    }
-  }
-
-  Future<void> _openPage() async {
-    await Clipboard.setData(ClipboardData(text: widget.device.userCode));
-    await launchUrl(
-      Uri.parse(widget.device.verificationUri),
-      mode: LaunchMode.externalApplication,
-    );
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    return AlertDialog(
-      title: const Text('Authorize on GitHub'),
-      content: Column(
-        mainAxisSize: MainAxisSize.min,
-        crossAxisAlignment: CrossAxisAlignment.start,
         children: [
-          const Text('Enter this code on GitHub:'),
-          const SizedBox(height: 8),
-          SelectableText(
-            widget.device.userCode,
-            style: Theme.of(context).textTheme.headlineSmall,
-          ),
-          const SizedBox(height: 16),
-          if (_error == null)
-            const Row(
-              children: [
-                SizedBox(
-                  width: 16,
-                  height: 16,
-                  child: CircularProgressIndicator(strokeWidth: 2),
+          ListTile(
+            contentPadding: EdgeInsets.zero,
+            title: const Text('Sync settings'),
+            subtitle: const Text('Firebase sync'),
+            trailing: const Icon(Icons.chevron_right),
+            onTap: () => Navigator.of(context).push<void>(
+              MaterialPageRoute(
+                builder: (_) => SyncSettingsScreen(
+                  accountLoader: loadAccount,
+                  accountSaver: saveAccount,
+                  accountClearer: clearAccount,
+                  sessionProbe: isFirebaseConfigured,
+                  firebaseFactory: openFirebase,
+                  googleFirebaseFactory: openFirebaseWithGoogle,
+                  googleAvailable: googleSignInSupported,
                 ),
-                SizedBox(width: 12),
-                Expanded(child: Text('Waiting for authorization…')),
-              ],
-            )
-          else
-            Text(
-              _error!,
-              style: TextStyle(color: Theme.of(context).colorScheme.error),
+              ),
             ),
+          ),
+          ListTile(
+            contentPadding: EdgeInsets.zero,
+            title: const Text('Advanced sync (GitHub)'),
+            subtitle: const Text('Cutover mirror — not recommended'),
+            trailing: const Icon(Icons.chevron_right),
+            onTap: () => Navigator.of(context).push<void>(
+              MaterialPageRoute(builder: (_) => const GitHubMirrorScreen()),
+            ),
+          ),
         ],
       ),
-      actions: [
-        TextButton(
-          onPressed: () => Navigator.of(context).pop(),
-          child: const Text('Cancel'),
-        ),
-        FilledButton.icon(
-          onPressed: _openPage,
-          icon: const Icon(Icons.open_in_new),
-          label: const Text('Open GitHub & copy code'),
-        ),
-      ],
     );
   }
 }
diff --git a/phone_app/pubspec.lock b/phone_app/pubspec.lock
index f602371..42904c2 100644
--- a/phone_app/pubspec.lock
+++ b/phone_app/pubspec.lock
@@ -598,6 +598,15 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.4.1"
+  sync_settings_ui:
+    dependency: "direct main"
+    description:
+      path: sync_settings_ui
+      ref: "sync_settings_ui-v0.1.0"
+      resolved-ref: "23c693da4e6fd6004df09829a7d75365dc086c2c"
+      url: "https://github.com/kuhyx/utils"
+    source: git
+    version: "0.1.0"
   term_glyph:
     dependency: transitive
     description:
diff --git a/phone_app/pubspec.yaml b/phone_app/pubspec.yaml
index 3a4842d..db0ba32 100644
--- a/phone_app/pubspec.yaml
+++ b/phone_app/pubspec.yaml
@@ -26,6 +26,15 @@ dependencies:
   path: ^1.9.0
   path_provider: ^2.1.0
   shared_preferences: ^2.3.0
+
+  # Shared "Sync settings" screen (Firebase + optional local backup), reused
+  # across every kuhy app that syncs. GitHub mirror stays app-local (see
+  # lib/screens/github_mirror_screen.dart).
+  sync_settings_ui:
+    git:
+      url: https://github.com/kuhyx/utils
+      ref: sync_settings_ui-v0.1.0
+      path: sync_settings_ui
   url_launcher: ^6.3.0
   uuid: ^4.6.0
 
diff --git a/phone_app/test/settings_screen_test.dart b/phone_app/test/settings_screen_test.dart
new file mode 100644
index 0000000..2ec5017
--- /dev/null
+++ b/phone_app/test/settings_screen_test.dart
@@ -0,0 +1,22 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:wake_alarm_sync/screens/github_mirror_screen.dart';
+import 'package:wake_alarm_sync/screens/settings_screen.dart';
+
+void main() {
+  testWidgets('shows the two sync links and navigates to each', (
+    tester,
+  ) async {
+    await tester.pumpWidget(
+      const MaterialApp(home: SettingsScreen()),
+    );
+
+    expect(find.text('Sync settings'), findsOneWidget);
+    expect(find.text('Advanced sync (GitHub)'), findsOneWidget);
+
+    await tester.tap(find.text('Advanced sync (GitHub)'));
+    await tester.pumpAndSettle();
+
+    expect(find.byType(GitHubMirrorScreen), findsOneWidget);
+  });
+}