diff --git a/app/lib/app/services/app_service.dart b/app/lib/app/services/app_service.dart
index 02314588..77556394 100644
--- a/app/lib/app/services/app_service.dart
+++ b/app/lib/app/services/app_service.dart
@@ -13,15 +13,15 @@ final class AppService {
   final PreferencesStorage storage;
 
   Locale get init {
-    final code = storage.readString(key: AppConst.localeKey);
+    final code = storage.readString(key: StorageKeys.localeKey);
     if (code != null) return Locale(code);
     // ignore: deprecated_member_use
     final deviceLocal = window.locale.languageCode;
-    return AppLocalizations.delegate.isSupported(Locale(deviceLocal)) ? Locale(deviceLocal) : const Locale('en');
+    return AppLocalizationHelper.getSupportedLocale(deviceLocal);
   }
 
   Future<Locale> setLocale(String langKey) async {
-    await storage.writeString(key: AppConst.localeKey, value: langKey);
+    await storage.writeString(key: StorageKeys.localeKey, value: langKey);
     return Locale(langKey);
   }
 }
diff --git a/app/lib/app/services/auth_service.dart b/app/lib/app/services/auth_service.dart
index e024ce59..74eb66ca 100644
--- a/app/lib/app/services/auth_service.dart
+++ b/app/lib/app/services/auth_service.dart
@@ -14,9 +14,9 @@ final class AuthService {
   final RemoteClient client;
 
   User? get init {
-    final userToken = storage.readString(key: AppConst.tokenKey);
-    final userGender = storage.readString(key: AppConst.genderKey);
-    final username = storage.readString(key: AppConst.usernameKey);
+    final userToken = storage.readString(key: StorageKeys.tokenKey);
+    final userGender = storage.readString(key: StorageKeys.genderKey);
+    final username = storage.readString(key: StorageKeys.usernameKey);
     if (userToken == null && userGender == null && username == null) return null;
     return User(
       accessToken: userToken!,
@@ -25,7 +25,7 @@ final class AuthService {
     );
   }
 
-  String? getToken() => storage.readString(key: AppConst.tokenKey);
+  String? getToken() => storage.readString(key: StorageKeys.tokenKey);
 
   Future<Either<User, Exception>> login(String languageCode, Gender gender) async {
     final user = await client.post<User>(
@@ -41,15 +41,18 @@ final class AuthService {
       Left.new,
       (r) async {
         final user = r.copyWith(gender: gender);
-        await storage.writeString(key: AppConst.tokenKey, value: user.accessToken);
-        await storage.writeString(key: AppConst.genderKey, value: user.gender!.name);
-        await storage.writeString(key: AppConst.usernameKey, value: user.username);
+        await Future.wait([
+          storage.writeString(key: StorageKeys.tokenKey, value: user.accessToken),
+          storage.writeString(key: StorageKeys.genderKey, value: user.gender!.name),
+          storage.writeString(key: StorageKeys.usernameKey, value: user.username),
+        ]);
+
         return Right(user);
       },
     );
   }
 
   Future<void> changeGender(Gender gender) async {
-    await storage.writeString(key: AppConst.genderKey, value: gender.name);
+    await storage.writeString(key: StorageKeys.genderKey, value: gender.name);
   }
 }
diff --git a/app/lib/app/services/theme_service.dart b/app/lib/app/services/theme_service.dart
index 451fcfad..295cd61f 100644
--- a/app/lib/app/services/theme_service.dart
+++ b/app/lib/app/services/theme_service.dart
@@ -1,17 +1,17 @@
 import 'package:flutter/material.dart';
 import 'package:mq_storage/mq_storage.dart';
 import 'package:my_quran/constants/contants.dart';
-
 import 'package:my_quran/theme/theme.dart';
 
-class ThemeService {
+@immutable
+final class ThemeService {
   const ThemeService(this.storage);
 
   final PreferencesStorage storage;
 
   CustomTheme get init {
-    final isDark = storage.readBool(key: AppConst.modeKey);
-    final cachedColorIndex = storage.readInt(key: AppConst.colorKey);
+    final isDark = storage.readBool(key: StorageKeys.modeKey);
+    final cachedColorIndex = storage.readInt(key: StorageKeys.colorKey);
     return switch (isDark) {
       true => CustomTheme(Brightness.dark, _getColor(cachedColorIndex)),
       _ => CustomTheme(Brightness.light, _getColor(cachedColorIndex)),
@@ -23,10 +23,10 @@ class ThemeService {
   }
 
   Future<void> setColor(int index) async {
-    await storage.writeInt(key: AppConst.colorKey, value: index);
+    await storage.writeInt(key: StorageKeys.colorKey, value: index);
   }
 
   Future<void> setMode({required bool isDark}) async {
-    await storage.writeBool(key: AppConst.modeKey, value: isDark);
+    await storage.writeBool(key: StorageKeys.modeKey, value: isDark);
   }
 }
diff --git a/app/lib/app_observer.dart b/app/lib/app_observer.dart
index 5fd8fbe7..d8ae21a2 100644
--- a/app/lib/app_observer.dart
+++ b/app/lib/app_observer.dart
@@ -1,29 +1,31 @@
-import 'dart:developer';
-
 import 'package:flutter_bloc/flutter_bloc.dart';
 
 class AppBlocObserver extends BlocObserver {
+  const AppBlocObserver({this.onLog});
+
+  final void Function(String log)? onLog;
+
   @override
   void onCreate(BlocBase<dynamic> bloc) {
     super.onCreate(bloc);
-    log('onCreate(${bloc.state})');
+    onLog?.call('onCreate(${bloc.state})');
   }
 
   @override
   void onChange(BlocBase<dynamic> bloc, Change<dynamic> change) {
     super.onChange(bloc, change);
-    log('onChange(${bloc.runtimeType}, $change)');
+    onLog?.call('onChange(${bloc.runtimeType}, $change)');
   }
 
   @override
   void onError(BlocBase<dynamic> bloc, Object error, StackTrace stackTrace) {
-    log('onError(${bloc.runtimeType}, $error, $stackTrace)');
+    onLog?.call('onError(${bloc.runtimeType}, $error, $stackTrace)');
     super.onError(bloc, error, stackTrace);
   }
 
   @override
   void onClose(BlocBase<dynamic> bloc) {
     super.onClose(bloc);
-    log('onClose(${bloc.runtimeType})');
+    onLog?.call('onClose(${bloc.runtimeType})');
   }
 }
diff --git a/app/lib/components/card/select_lang_list.dart b/app/lib/components/card/select_lang_list.dart
index 6cc49740..4c8dd1ed 100644
--- a/app/lib/components/card/select_lang_list.dart
+++ b/app/lib/components/card/select_lang_list.dart
@@ -1,9 +1,8 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:mq_ci_keys/mq_ci_keys.dart';
-
 import 'package:my_quran/app/app.dart';
-import 'package:my_quran/constants/contants.dart';
+import 'package:my_quran/l10n/l10.dart';
 
 class SelectLangFromListViewBuilder extends StatelessWidget {
   const SelectLangFromListViewBuilder({super.key});
@@ -13,10 +12,10 @@ class SelectLangFromListViewBuilder extends StatelessWidget {
     final appCubit = context.watch<AppCubit>();
     final colorScheme = Theme.of(context).colorScheme;
     return ListView.builder(
-      itemCount: AppConst.locales.length,
+      itemCount: AppLocalizationHelper.locales.length,
       itemBuilder: (BuildContext context, int index) {
-        final locale = AppConst.locales[index];
-        final langName = AppConst.getName(locale.toLanguageTag());
+        final locale = AppLocalizationHelper.locales[index];
+        final langName = AppLocalizationHelper.getName(locale.toLanguageTag());
         return Card(
           child: ListTile(
             key: Key(MqKeys.languageCode(locale.languageCode)),
diff --git a/app/lib/constants/app/app_const.dart b/app/lib/constants/app/app_const.dart
deleted file mode 100644
index 64b6b41a..00000000
--- a/app/lib/constants/app/app_const.dart
+++ /dev/null
@@ -1,84 +0,0 @@
-import 'package:flutter/material.dart';
-import 'package:my_quran/config/app_config.dart';
-
-class AppConst {
-  const AppConst._();
-
-  static const bismallah = 'بِسْمِ ٱللَّهِ ٱلرَّحْمَـٰنِ ٱلرَّحِيمِ';
-  static const sajdaSymbol = '۩';
-  static const sajdaAyats = [1160, 1722, 1951, 2138, 2308, 2613, 2672, 2915, 3185, 3518, 3994, 4256, 4846, 5905, 6125];
-
-  /* 
-  yes - https://api.quran.com/api/v4/quran/verses/uthmanit?page_number=1 has sajda symbol ۩
-  correct - check from mushaf
-  1. 1160(ayat id) - 176 page - аль-Араф:206 (yes) (correct)
-  2. 1722(ayat id) - 251 page - ар-Рад:15 (yes) (correct)
-  3. 1951(ayat id) - 272 page - ан-Нахль:50 (yes) (correct)
-  4. 2138(ayat id) - 293 page - аль-Исра:109  (yes) (correct)
-  5. 2308(ayat id) - 309 page - Марьям:58 (yes) (correct)
-  6. 2613(ayat id) - 334 page - аль-Хадж:18 (yes) (correct)
-  7. 2672(ayat id) - 341 page - аль-Хадж:77 (yes) (correct)
-  8. 2915(ayat id) - 365 page - аль-Фуркан:60 (yes) (correct)
-  9. 3185(ayat id) - 379 page - ан-Намль:26 (yes) (correct)
-  10. 3518(ayat id) - 416 page - ас-Сажда:15 (yes) (correct)
-  11. 3994(ayat id) - 454 page - Сад:24 (yes) (correct)
-  12. 4256(ayat id) - 480 page - Фуссилят:38 (yes) (correct)
-  13. 4846(ayat id) - 528 page - ан-Наджм:62 (yes) (correct)
-  14. 5905(ayat id) - 589 page - аль-Иншикак:21 (yes) (correct)
-  16. 6125(ayat id) - 597 page - аль-Аляк:19 (yes) (correct)
-  */
-
-  static String get localeKey => apiConst.isDevmode ? _localeKeyDev : _localeKey;
-  static String get tokenKey => apiConst.isDevmode ? _tokenKeyDev : _tokenKey;
-  static String get genderKey => apiConst.isDevmode ? _genderKeyDev : _genderKey;
-  static String get usernameKey => apiConst.isDevmode ? _usernameKeyDev : _usernameKey;
-  static String get modeKey => apiConst.isDevmode ? _modeKeyDev : _modeKey;
-  static String get readThemeKey => apiConst.isDevmode ? _readThemeKeyDev : _readThemeKey;
-  static String get colorKey => apiConst.isDevmode ? _colorKeyDev : _colorKey;
-
-  static const _localeKey = 'locale';
-  static const _tokenKey = 'token';
-  static const _genderKey = 'gender';
-  static const _usernameKey = 'username';
-  static const _modeKey = 'mode';
-  static const _readThemeKey = 'readThemeKey';
-  static const _colorKey = 'color';
-
-  static const _localeKeyDev = 'locale-dev';
-  static const _tokenKeyDev = 'token-dev';
-  static const _genderKeyDev = 'gender-dev';
-  static const _usernameKeyDev = 'username-dev';
-  static const _modeKeyDev = 'mode-dev';
-  static const _readThemeKeyDev = 'readThemeKey-dev';
-  static const _colorKeyDev = 'color-dev';
-
-  static const locales = <Locale>[
-    Locale('en'),
-    Locale('ky'),
-    Locale('kk'),
-    Locale('tr'),
-    Locale('ar'),
-    Locale('id'),
-    Locale('ru'),
-  ];
-
-  static String getName(String code) {
-    return switch (code) {
-      'en' => 'English',
-      'ky' => 'Кыргызча',
-      'tr' => 'Türkçe',
-      'kk' => 'Қазақша',
-      'ru' => 'Русский',
-      'id' => 'Indonesia',
-      'ar' => 'العربية',
-      _ => 'English',
-    };
-  }
-
-  static bool isLocalSupport(String deviceLocal) {
-    return switch (deviceLocal) {
-      'en' || 'ky' || 'tr' || 'kk' || 'ru' || 'id' || 'ar' => true,
-      _ => false,
-    };
-  }
-}
diff --git a/app/lib/constants/contants.dart b/app/lib/constants/contants.dart
index 20b35255..bfb1ec36 100644
--- a/app/lib/constants/contants.dart
+++ b/app/lib/constants/contants.dart
@@ -1,4 +1,5 @@
 export 'api/api_const.dart';
-export 'app/app_const.dart';
 export 'assets/assets.gen.dart';
 export 'assets/fonts.gen.dart';
+export 'keys/storage_keys.dart';
+export 'static/app_static.dart';
diff --git a/app/lib/constants/keys/storage_keys.dart b/app/lib/constants/keys/storage_keys.dart
new file mode 100644
index 00000000..1e2d63f1
--- /dev/null
+++ b/app/lib/constants/keys/storage_keys.dart
@@ -0,0 +1,31 @@
+import 'package:meta/meta.dart';
+import 'package:my_quran/config/config.dart';
+
+@immutable
+final class StorageKeys {
+  const StorageKeys._();
+
+  static String get localeKey => apiConst.isDevmode ? _localeKeyDev : _localeKey;
+  static String get tokenKey => apiConst.isDevmode ? _tokenKeyDev : _tokenKey;
+  static String get genderKey => apiConst.isDevmode ? _genderKeyDev : _genderKey;
+  static String get usernameKey => apiConst.isDevmode ? _usernameKeyDev : _usernameKey;
+  static String get modeKey => apiConst.isDevmode ? _modeKeyDev : _modeKey;
+  static String get readThemeKey => apiConst.isDevmode ? _readThemeKeyDev : _readThemeKey;
+  static String get colorKey => apiConst.isDevmode ? _colorKeyDev : _colorKey;
+
+  static const _localeKey = 'locale';
+  static const _tokenKey = 'token';
+  static const _genderKey = 'gender';
+  static const _usernameKey = 'username';
+  static const _modeKey = 'mode';
+  static const _readThemeKey = 'readThemeKey';
+  static const _colorKey = 'color';
+
+  static const _localeKeyDev = 'locale-dev';
+  static const _tokenKeyDev = 'token-dev';
+  static const _genderKeyDev = 'gender-dev';
+  static const _usernameKeyDev = 'username-dev';
+  static const _modeKeyDev = 'mode-dev';
+  static const _readThemeKeyDev = 'readThemeKey-dev';
+  static const _colorKeyDev = 'color-dev';
+}
diff --git a/app/lib/constants/static/app_static.dart b/app/lib/constants/static/app_static.dart
new file mode 100644
index 00000000..5ec33aec
--- /dev/null
+++ b/app/lib/constants/static/app_static.dart
@@ -0,0 +1,46 @@
+import 'package:meta/meta.dart';
+
+@immutable
+final class AppStatic {
+  const AppStatic._();
+
+  static const bismallah = 'بِسْمِ ٱللَّهِ ٱلرَّحْمَـٰنِ ٱلرَّحِيمِ';
+  static const sajdaSymbol = '۩';
+  static const sajdaAyats = [
+    1160,
+    1722,
+    1951,
+    2138,
+    2308,
+    2613,
+    2672,
+    2915,
+    3185,
+    3518,
+    3994,
+    4256,
+    4846,
+    5905,
+    6125,
+  ];
+
+  /* 
+  yes - https://api.quran.com/api/v4/quran/verses/uthmanit?page_number=1 has sajda symbol ۩
+  correct - check from mushaf
+  1. 1160(ayat id) - 176 page - аль-Араф:206 (yes) (correct)
+  2. 1722(ayat id) - 251 page - ар-Рад:15 (yes) (correct)
+  3. 1951(ayat id) - 272 page - ан-Нахль:50 (yes) (correct)
+  4. 2138(ayat id) - 293 page - аль-Исра:109  (yes) (correct)
+  5. 2308(ayat id) - 309 page - Марьям:58 (yes) (correct)
+  6. 2613(ayat id) - 334 page - аль-Хадж:18 (yes) (correct)
+  7. 2672(ayat id) - 341 page - аль-Хадж:77 (yes) (correct)
+  8. 2915(ayat id) - 365 page - аль-Фуркан:60 (yes) (correct)
+  9. 3185(ayat id) - 379 page - ан-Намль:26 (yes) (correct)
+  10. 3518(ayat id) - 416 page - ас-Сажда:15 (yes) (correct)
+  11. 3994(ayat id) - 454 page - Сад:24 (yes) (correct)
+  12. 4256(ayat id) - 480 page - Фуссилят:38 (yes) (correct)
+  13. 4846(ayat id) - 528 page - ан-Наджм:62 (yes) (correct)
+  14. 5905(ayat id) - 589 page - аль-Иншикак:21 (yes) (correct)
+  16. 6125(ayat id) - 597 page - аль-Аляк:19 (yes) (correct)
+  */
+}
diff --git a/app/lib/core/client/remote_client.dart b/app/lib/core/client/remote_client.dart
index 37514c2c..846c12a4 100644
--- a/app/lib/core/client/remote_client.dart
+++ b/app/lib/core/client/remote_client.dart
@@ -40,7 +40,7 @@ class RemoteClient {
 
       /// if an Unauthorized  return Authentication Exception
     } else if (response.statusCode == 401) {
-      return const Left(AuthenticationException());
+      return const Left(AuthenticationExc());
     } else {
       /// if the response is not successful and unauthorized, it will return a server exception
       return const Left(ServerExc('server exception'));
diff --git a/app/lib/core/core.dart b/app/lib/core/core.dart
index 33878be5..4a43d4f9 100644
--- a/app/lib/core/core.dart
+++ b/app/lib/core/core.dart
@@ -1,9 +1,9 @@
 export 'client/network_client.dart';
 export 'client/remote_client.dart';
+export 'either/either.dart';
 export 'exceptions/network_exception.dart';
 export 'exceptions/server_exception.dart';
 export 'exceptions/auth_exception.dart';
 export 'exceptions/convert_exception.dart';
 export 'launch/app_launch.dart';
-export 'interface/either.dart';
 export 'enums/fetch_status.dart';
diff --git a/app/lib/core/interface/either.dart b/app/lib/core/either/either.dart
similarity index 97%
rename from app/lib/core/interface/either.dart
rename to app/lib/core/either/either.dart
index c9f7c401..e46f4281 100644
--- a/app/lib/core/interface/either.dart
+++ b/app/lib/core/either/either.dart
@@ -49,7 +49,7 @@ abstract class Either<R, L> {
 /// }
 /// ```
 @immutable
-class Right<R, L> extends Either<R, L> {
+final class Right<R, L> extends Either<R, L> {
   const Right(this.r);
 
   /// A field is defined to hold the right value.
@@ -62,6 +62,7 @@ class Right<R, L> extends Either<R, L> {
   /// Equality check is defined for operator == and hashCode is computed for hashing.
   @override
   bool operator ==(Object other) => other is Right && other.r == r;
+
   @override
   int get hashCode => r.hashCode;
 }
@@ -81,7 +82,7 @@ class Right<R, L> extends Either<R, L> {
 /// }
 /// ```
 @immutable
-class Left<R, L> extends Either<R, L> {
+final class Left<R, L> extends Either<R, L> {
   const Left(this.l);
 
   /// A field is defined to hold the left value.
@@ -94,6 +95,7 @@ class Left<R, L> extends Either<R, L> {
   /// Equality check is defined for operator == and hashCode is computed for hashing.
   @override
   bool operator ==(Object other) => other is Left && other.l == l;
+
   @override
   int get hashCode => l.hashCode;
 }
diff --git a/app/lib/core/exceptions/auth_exception.dart b/app/lib/core/exceptions/auth_exception.dart
index 2cf96f58..9b56b976 100644
--- a/app/lib/core/exceptions/auth_exception.dart
+++ b/app/lib/core/exceptions/auth_exception.dart
@@ -1,6 +1,8 @@
-/// Auhtentication Exception
-class AuthenticationException implements Exception {
-  const AuthenticationException({this.message});
+import 'package:meta/meta.dart';
+
+@immutable
+final class AuthenticationExc implements Exception {
+  const AuthenticationExc({this.message});
 
   final String? message;
 
diff --git a/app/lib/core/exceptions/convert_exception.dart b/app/lib/core/exceptions/convert_exception.dart
index d41b8494..c60570c1 100644
--- a/app/lib/core/exceptions/convert_exception.dart
+++ b/app/lib/core/exceptions/convert_exception.dart
@@ -1,5 +1,7 @@
-/// Convert Exception
-class ConvertExc implements Exception {
+import 'package:meta/meta.dart';
+
+@immutable
+final class ConvertExc implements Exception {
   const ConvertExc({this.message});
 
   final String? message;
diff --git a/app/lib/core/exceptions/network_exception.dart b/app/lib/core/exceptions/network_exception.dart
index 4d064139..f201ddb4 100644
--- a/app/lib/core/exceptions/network_exception.dart
+++ b/app/lib/core/exceptions/network_exception.dart
@@ -1,4 +1,7 @@
-class NetworkExc implements Exception {
+import 'package:meta/meta.dart';
+
+@immutable
+final class NetworkExc implements Exception {
   const NetworkExc([this.massage]);
 
   final String? massage;
diff --git a/app/lib/core/exceptions/server_exception.dart b/app/lib/core/exceptions/server_exception.dart
index 9a0858c4..bfb07228 100644
--- a/app/lib/core/exceptions/server_exception.dart
+++ b/app/lib/core/exceptions/server_exception.dart
@@ -1,4 +1,7 @@
-class ServerExc implements Exception {
+import 'package:meta/meta.dart';
+
+@immutable
+final class ServerExc implements Exception {
   const ServerExc(this.massage);
 
   final String? massage;
diff --git a/app/lib/core/launch/app_launch.dart b/app/lib/core/launch/app_launch.dart
index 5b8371fe..43e99609 100644
--- a/app/lib/core/launch/app_launch.dart
+++ b/app/lib/core/launch/app_launch.dart
@@ -5,7 +5,13 @@ import 'package:url_launcher/url_launcher.dart';
 
 @immutable
 final class AppLaunch {
-  static Future<void> sendEmail(String email, {String? snackBarText, BuildContext? context}) async {
+  const AppLaunch._();
+
+  static Future<void> sendEmail(
+    String email, {
+    String? snackBarText,
+    BuildContext? context,
+  }) async {
     try {
       final isSuccess = await launchUrl(Uri(scheme: 'mailto', path: email));
       if (!isSuccess && snackBarText != null && context != null && context.mounted) {
@@ -16,7 +22,11 @@ final class AppLaunch {
     }
   }
 
-  static Future<void> sendTelegram(String username, {String? snackBarText, BuildContext? context}) async {
+  static Future<void> sendTelegram(
+    String username, {
+    String? snackBarText,
+    BuildContext? context,
+  }) async {
     try {
       final isSuccess = await launchUrl(
         Uri.parse('https://telegram.me/$username'),
@@ -30,7 +40,11 @@ final class AppLaunch {
     }
   }
 
-  static Future<void> sendWhatsApp(String whatsapp, {String? snackBarText, BuildContext? context}) async {
+  static Future<void> sendWhatsApp(
+    String whatsapp, {
+    String? snackBarText,
+    BuildContext? context,
+  }) async {
     try {
       final isSuccess = await launchUrl(
         Uri.parse('whatsapp://send?phone=$whatsapp'),
@@ -44,7 +58,11 @@ final class AppLaunch {
     }
   }
 
-  static Future<void> launchURL(String url, {String? snackBarText, BuildContext? context}) async {
+  static Future<void> launchURL(
+    String url, {
+    String? snackBarText,
+    BuildContext? context,
+  }) async {
     try {
       final isSuccess = await launchUrl(Uri.parse(url));
       if (!isSuccess && snackBarText != null && context != null && context.mounted) {
diff --git a/app/lib/l10n/l10.dart b/app/lib/l10n/l10.dart
index 17c891b5..9a24d132 100644
--- a/app/lib/l10n/l10.dart
+++ b/app/lib/l10n/l10.dart
@@ -6,3 +6,42 @@ export 'package:flutter_gen/gen_l10n/app_localizations.dart';
 extension AppLocalizationsX on BuildContext {
   AppLocalizations get l10n => AppLocalizations.of(this);
 }
+
+final class AppLocalizationHelper {
+  const AppLocalizationHelper._();
+
+  static const locales = <Locale>[
+    Locale('en'),
+    Locale('ky'),
+    Locale('kk'),
+    Locale('tr'),
+    Locale('ar'),
+    Locale('id'),
+    Locale('ru'),
+  ];
+
+  static String getName(String code) {
+    return switch (code) {
+      'en' => 'English',
+      'ky' => 'Кыргызча',
+      'tr' => 'Türkçe',
+      'kk' => 'Қазақша',
+      'ru' => 'Русский',
+      'id' => 'Indonesia',
+      'ar' => 'العربية',
+      _ => 'English',
+    };
+  }
+
+  static bool isSupported(String locale) {
+    return switch (locale) {
+      'en' || 'ky' || 'tr' || 'kk' || 'ru' || 'id' || 'ar' => true,
+      _ => false,
+    };
+  }
+
+  static Locale getSupportedLocale(String locale) {
+    if (isSupported(locale)) return Locale(locale);
+    return const Locale('en');
+  }
+}
diff --git a/app/lib/main.dart b/app/lib/main.dart
index 53f970ff..58f03a2b 100644
--- a/app/lib/main.dart
+++ b/app/lib/main.dart
@@ -25,7 +25,7 @@ Future<void> main({AppConfig? appConfig}) async {
     androidNotificationIcon: 'mipmap/launcher_icon',
   );
 
-  Bloc.observer = AppBlocObserver();
+  Bloc.observer = const AppBlocObserver(onLog: log);
   final storage = await PreferencesStorage.getInstance();
 
   appConfig ??= AppConfig(storage: storage);
diff --git a/app/lib/modules/home/data/model/home_model_response.dart b/app/lib/modules/home/data/model/home_model_response.dart
index dc4fe334..45d636bf 100644
--- a/app/lib/modules/home/data/model/home_model_response.dart
+++ b/app/lib/modules/home/data/model/home_model_response.dart
@@ -1,9 +1,11 @@
+import 'package:flutter/material.dart';
 import 'package:json_annotation/json_annotation.dart';
 
 part 'home_model_response.g.dart';
 
 @JsonSerializable()
-class HomeModelResponse {
+@immutable
+final class HomeModelResponse {
   const HomeModelResponse({
     required this.allDoneHatims,
     required this.allDonePages,
diff --git a/app/lib/modules/home/data/repository/home_repository_impl.dart b/app/lib/modules/home/data/repository/home_repository_impl.dart
index 462e85ed..89c76800 100644
--- a/app/lib/modules/home/data/repository/home_repository_impl.dart
+++ b/app/lib/modules/home/data/repository/home_repository_impl.dart
@@ -1,8 +1,10 @@
 import 'dart:developer';
 
+import 'package:flutter/material.dart';
 import 'package:my_quran/modules/modules.dart';
 
-class HomeRepositoryImpl implements HomeRepository {
+@immutable
+final class HomeRepositoryImpl implements HomeRepository {
   const HomeRepositoryImpl(
     this.localDataSource,
     this.remoteDataSource,
diff --git a/app/lib/modules/home/data/source/home_local_data_source.dart b/app/lib/modules/home/data/source/home_local_data_source.dart
index 8806c20e..059097d5 100644
--- a/app/lib/modules/home/data/source/home_local_data_source.dart
+++ b/app/lib/modules/home/data/source/home_local_data_source.dart
@@ -1,8 +1,10 @@
 import 'dart:convert';
+import 'package:flutter/material.dart';
 import 'package:mq_storage/mq_storage.dart';
 import 'package:my_quran/modules/modules.dart';
 
-class HomeLocalDataSource {
+@immutable
+final class HomeLocalDataSource {
   const HomeLocalDataSource(this.storage);
 
   final PreferencesStorage storage;
diff --git a/app/lib/modules/home/data/source/home_remote_data_source.dart b/app/lib/modules/home/data/source/home_remote_data_source.dart
index 64b7ef84..a0f752e7 100644
--- a/app/lib/modules/home/data/source/home_remote_data_source.dart
+++ b/app/lib/modules/home/data/source/home_remote_data_source.dart
@@ -1,8 +1,10 @@
+import 'package:flutter/material.dart';
 import 'package:my_quran/config/config.dart';
 import 'package:my_quran/core/core.dart';
 import 'package:my_quran/modules/modules.dart';
 
-class HomeRemoteDataSource {
+@immutable
+final class HomeRemoteDataSource {
   const HomeRemoteDataSource(this.remoteClient);
 
   final RemoteClient remoteClient;
diff --git a/app/lib/modules/home/domain/entity/home_entity.dart b/app/lib/modules/home/domain/entity/home_entity.dart
index 1082155f..f281db42 100644
--- a/app/lib/modules/home/domain/entity/home_entity.dart
+++ b/app/lib/modules/home/domain/entity/home_entity.dart
@@ -1,4 +1,7 @@
-class HomeEntity {
+import 'package:flutter/material.dart';
+
+@immutable
+final class HomeEntity {
   const HomeEntity({
     required this.allDoneHatims,
     required this.allDonePages,
diff --git a/app/lib/modules/home/domain/usecase/get_data_usecase.dart b/app/lib/modules/home/domain/usecase/get_data_usecase.dart
index b12bb4d8..7aed328f 100644
--- a/app/lib/modules/home/domain/usecase/get_data_usecase.dart
+++ b/app/lib/modules/home/domain/usecase/get_data_usecase.dart
@@ -1,6 +1,8 @@
+import 'package:flutter/material.dart';
 import 'package:my_quran/modules/modules.dart';
 
-class GetHomeDataUseCase {
+@immutable
+final class GetHomeDataUseCase {
   const GetHomeDataUseCase(this.repository);
 
   final HomeRepository repository;
diff --git a/app/lib/modules/home/presentation/cubit/home_cubit.dart b/app/lib/modules/home/presentation/cubit/home_cubit.dart
index 7752b898..63e45802 100644
--- a/app/lib/modules/home/presentation/cubit/home_cubit.dart
+++ b/app/lib/modules/home/presentation/cubit/home_cubit.dart
@@ -1,4 +1,5 @@
 import 'package:equatable/equatable.dart';
+import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:my_quran/core/core.dart';
 import 'package:my_quran/modules/modules.dart';
diff --git a/app/lib/modules/home/presentation/cubit/home_state.dart b/app/lib/modules/home/presentation/cubit/home_state.dart
index 5da04e45..975cddf9 100644
--- a/app/lib/modules/home/presentation/cubit/home_state.dart
+++ b/app/lib/modules/home/presentation/cubit/home_state.dart
@@ -1,6 +1,7 @@
 part of 'home_cubit.dart';
 
-class HomeState extends Equatable {
+@immutable
+final class HomeState extends Equatable {
   const HomeState({
     this.status = FetchStatus.loading,
     this.homeModel,
diff --git a/app/lib/modules/read/data/source/local_theme_data_source.dart b/app/lib/modules/read/data/source/local_theme_data_source.dart
index ea1c80b7..26019c2c 100644
--- a/app/lib/modules/read/data/source/local_theme_data_source.dart
+++ b/app/lib/modules/read/data/source/local_theme_data_source.dart
@@ -11,12 +11,12 @@ final class LocalThemeDataSource {
   final PreferencesStorage storage;
 
   ReadThemeState get initialTheme {
-    final value = storage.readString(key: AppConst.readThemeKey);
+    final value = storage.readString(key: StorageKeys.readThemeKey);
     return value != null ? ReadThemeState.fromJson(json.decode(value) as Map<String, dynamic>) : const ReadThemeState();
   }
 
   Future<void> saveThemeState(ReadThemeState themeState) async {
     final value = json.encode(themeState.toJson());
-    await storage.writeString(key: AppConst.readThemeKey, value: value);
+    await storage.writeString(key: StorageKeys.readThemeKey, value: value);
   }
 }
diff --git a/app/lib/modules/read/domain/entity/quran_page_entity.dart b/app/lib/modules/read/domain/entity/quran_page_entity.dart
index 4719fdd7..793bb89a 100644
--- a/app/lib/modules/read/domain/entity/quran_page_entity.dart
+++ b/app/lib/modules/read/domain/entity/quran_page_entity.dart
@@ -17,7 +17,7 @@ final class QuranPageEntity {
       ..writeAll(
         verses.map(
           (e) =>
-              '${e.isFirst ? '\n\n${AppConst.bismallah.padLeft(50).padRight(50)}\n' : ''} ${e.textUthmani} ${e.hasSajda ? AppConst.sajdaSymbol : ''} \uFD3F${e.ayatNumber.toArabicDigits}\uFD3E',
+              '${e.isFirst ? '\n\n${AppStatic.bismallah.padLeft(50).padRight(50)}\n' : ''} ${e.textUthmani} ${e.hasSajda ? AppStatic.sajdaSymbol : ''} \uFD3F${e.ayatNumber.toArabicDigits}\uFD3E',
         ),
         '  ',
       );
diff --git a/app/lib/modules/read/domain/entity/verse_entity.dart b/app/lib/modules/read/domain/entity/verse_entity.dart
index 47e5641d..b8b92d3b 100644
--- a/app/lib/modules/read/domain/entity/verse_entity.dart
+++ b/app/lib/modules/read/domain/entity/verse_entity.dart
@@ -16,5 +16,5 @@ final class VerseEnity {
   int get juzNumber => int.parse(verseKey.split(':').first);
   int get ayatNumber => int.parse(verseKey.split(':').last);
   bool get isFirst => ayatNumber == 1;
-  bool get hasSajda => AppConst.sajdaAyats.contains(id);
+  bool get hasSajda => AppStatic.sajdaAyats.contains(id);
 }
diff --git a/app/lib/modules/read/presentation/view/read_view.dart b/app/lib/modules/read/presentation/view/read_view.dart
index 0753b8da..7b40c817 100644
--- a/app/lib/modules/read/presentation/view/read_view.dart
+++ b/app/lib/modules/read/presentation/view/read_view.dart
@@ -84,7 +84,7 @@ class ReadUI extends StatelessWidget {
               centerTitle: true,
               title: FittedBox(
                 child: Text(
-                  AppConst.bismallah,
+                  AppStatic.bismallah,
                   maxLines: 2,
                   textAlign: TextAlign.center,
                   style: TextStyle(
diff --git a/app/lib/modules/settings/view/settings_view.dart b/app/lib/modules/settings/view/settings_view.dart
index 9b0f80bb..e486cce9 100644
--- a/app/lib/modules/settings/view/settings_view.dart
+++ b/app/lib/modules/settings/view/settings_view.dart
@@ -4,7 +4,6 @@ import 'package:go_router/go_router.dart';
 import 'package:mq_ci_keys/mq_ci_keys.dart';
 
 import 'package:my_quran/app/app.dart';
-import 'package:my_quran/constants/contants.dart';
 import 'package:my_quran/l10n/l10.dart';
 import 'package:my_quran/models/models.dart';
 
@@ -45,7 +44,11 @@ class SettingsView extends StatelessWidget {
             trailing: Row(
               mainAxisSize: MainAxisSize.min,
               children: [
-                Text(AppConst.getName(appCubit.state.currentLocale.toLanguageTag())),
+                Text(
+                  AppLocalizationHelper.getName(
+                    appCubit.state.currentLocale.toLanguageTag(),
+                  ),
+                ),
                 const SizedBox(width: 17),
                 const Icon(Icons.arrow_forward_ios),
               ],
diff --git a/app/lib/theme/custom/color/app_colors.dart b/app/lib/theme/custom/color/app_colors.dart
index 63c58feb..beca906a 100644
--- a/app/lib/theme/custom/color/app_colors.dart
+++ b/app/lib/theme/custom/color/app_colors.dart
@@ -2,6 +2,8 @@ import 'package:flutter/material.dart';
 
 @immutable
 final class AppColors {
+  const AppColors._();
+
   static const Color white = Colors.white;
   static const Color black = Colors.black;
   static const Color red = Colors.red;
diff --git a/app/lib/theme/custom/component/componet_theme.dart b/app/lib/theme/custom/component/componet_theme.dart
index e48bf0d8..910f6fa6 100644
--- a/app/lib/theme/custom/component/componet_theme.dart
+++ b/app/lib/theme/custom/component/componet_theme.dart
@@ -3,55 +3,57 @@ import 'package:flutter/material.dart';
 mixin CompomnentTheme {
   ShapeBorder get shapeMedium => const RoundedRectangleBorder();
 
-  CardTheme cardTheme() {
+  ColorScheme get scheme;
+
+  CardTheme get cardTheme {
     return const CardTheme();
   }
 
-  ButtonThemeData buttonTheme(ColorScheme colors) {
+  ButtonThemeData get buttonTheme {
     return const ButtonThemeData();
   }
 
-  ElevatedButtonThemeData elevatedButtonThemeData(ColorScheme colors) {
+  ElevatedButtonThemeData get elevatedButtonThemeData {
     return ElevatedButtonThemeData(
       style: ElevatedButton.styleFrom(),
     );
   }
 
-  InputDecorationTheme inputDecorationTheme(ColorScheme colors) {
+  InputDecorationTheme get inputDecorationTheme {
     return const InputDecorationTheme(
       border: OutlineInputBorder(),
     );
   }
 
-  ListTileThemeData listTileTheme(ColorScheme colors) {
+  ListTileThemeData get listTileTheme {
     return const ListTileThemeData();
   }
 
-  AppBarTheme appBarTheme(ColorScheme colors) {
-    return AppBarTheme(backgroundColor: colors.surfaceVariant);
+  AppBarTheme get appBarTheme {
+    return AppBarTheme(backgroundColor: scheme.surfaceVariant);
   }
 
-  TabBarTheme tabBarTheme(ColorScheme colors) {
+  TabBarTheme get tabBarTheme {
     return const TabBarTheme();
   }
 
-  BottomAppBarTheme bottomAppBarTheme(ColorScheme colors) {
+  BottomAppBarTheme get bottomAppBarTheme {
     return const BottomAppBarTheme();
   }
 
-  BottomNavigationBarThemeData bottomNavigationBarTheme(ColorScheme colors) {
+  BottomNavigationBarThemeData get bottomNavigationBarTheme {
     return const BottomNavigationBarThemeData();
   }
 
-  NavigationRailThemeData navigationRailTheme(ColorScheme colors) {
+  NavigationRailThemeData get navigationRailTheme {
     return const NavigationRailThemeData();
   }
 
-  DrawerThemeData drawerTheme(ColorScheme colors) {
+  DrawerThemeData get drawerTheme {
     return const DrawerThemeData();
   }
 
-  ScrollbarThemeData scrollbarThemeData(ColorScheme colors) {
+  ScrollbarThemeData get scrollbarThemeData {
     return const ScrollbarThemeData();
   }
 }
diff --git a/app/lib/theme/custom/custom_theme.dart b/app/lib/theme/custom/custom_theme.dart
index 01fd61e0..56759a3a 100644
--- a/app/lib/theme/custom/custom_theme.dart
+++ b/app/lib/theme/custom/custom_theme.dart
@@ -1,54 +1,42 @@
 import 'package:flutter/material.dart';
 import 'package:my_quran/theme/theme.dart';
 
-class CustomTheme with CompomnentTheme {
+@immutable
+final class CustomTheme with CompomnentTheme {
   const CustomTheme(this.brightness, this.targetColor);
 
   final Brightness brightness;
   final Color targetColor;
 
-  ColorScheme colors() {
-    return ColorScheme.fromSeed(
-      seedColor: targetColor,
-      brightness: brightness,
-    );
-  }
+  @override
+  ColorScheme get scheme => ColorScheme.fromSeed(
+        seedColor: targetColor,
+        brightness: brightness,
+      );
 
-  ThemeData light() {
-    final scheme = colors();
-    return ThemeData.light().copyWith(
+  ThemeData get _base {
+    return ThemeData(
       colorScheme: scheme,
-      appBarTheme: appBarTheme(scheme),
-      cardTheme: cardTheme(),
-      listTileTheme: listTileTheme(scheme),
-      bottomAppBarTheme: bottomAppBarTheme(scheme),
-      bottomNavigationBarTheme: bottomNavigationBarTheme(scheme),
-      navigationRailTheme: navigationRailTheme(scheme),
-      tabBarTheme: tabBarTheme(scheme),
-      drawerTheme: drawerTheme(scheme),
-      buttonTheme: buttonTheme(scheme),
-      inputDecorationTheme: inputDecorationTheme(scheme),
-      elevatedButtonTheme: elevatedButtonThemeData(scheme),
-      scrollbarTheme: scrollbarThemeData(scheme),
+      appBarTheme: appBarTheme,
+      cardTheme: cardTheme,
+      listTileTheme: listTileTheme,
+      bottomAppBarTheme: bottomAppBarTheme,
+      bottomNavigationBarTheme: bottomNavigationBarTheme,
+      navigationRailTheme: navigationRailTheme,
+      tabBarTheme: tabBarTheme,
+      drawerTheme: drawerTheme,
+      buttonTheme: buttonTheme,
+      inputDecorationTheme: inputDecorationTheme,
+      elevatedButtonTheme: elevatedButtonThemeData,
+      scrollbarTheme: scrollbarThemeData,
     );
   }
 
-  ThemeData dark() {
-    final scheme = colors();
-    return ThemeData.dark().copyWith(
-      colorScheme: scheme,
-      appBarTheme: appBarTheme(scheme),
-      cardTheme: cardTheme(),
-      listTileTheme: listTileTheme(scheme),
-      bottomAppBarTheme: bottomAppBarTheme(scheme),
-      bottomNavigationBarTheme: bottomNavigationBarTheme(scheme),
-      navigationRailTheme: navigationRailTheme(scheme),
-      tabBarTheme: tabBarTheme(scheme),
-      drawerTheme: drawerTheme(scheme),
-    );
-  }
+  ThemeData get light => _base.copyWith(brightness: Brightness.light);
+
+  ThemeData get dark => _base.copyWith(brightness: Brightness.dark);
 
-  ThemeData get themeData => brightness == Brightness.dark ? dark() : light();
+  ThemeData get themeData => brightness == Brightness.dark ? dark : light;
 
   CustomTheme copyWith({Brightness? brightness, Color? targetColor}) {
     return CustomTheme(brightness ?? this.brightness, targetColor ?? this.targetColor);
diff --git a/app/test/widget_test.dart b/app/test/widget_test.dart
index a1226d32..71543bd5 100644
--- a/app/test/widget_test.dart
+++ b/app/test/widget_test.dart
@@ -2,7 +2,6 @@ import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:mocktail/mocktail.dart';
 import 'package:mq_storage/mq_storage.dart';
-
 import 'package:my_quran/app/app.dart';
 import 'package:my_quran/constants/contants.dart';
 import 'package:my_quran/core/core.dart';
@@ -32,11 +31,11 @@ void main() {
     final homeRepo = MockHomeRepositoryImpl();
     final themeService = ThemeService(storage);
 
-    when(() => storage.readString(key: AppConst.tokenKey)).thenReturn(null);
-    when(() => storage.readString(key: AppConst.genderKey)).thenReturn(null);
-    when(() => storage.readString(key: AppConst.localeKey)).thenReturn('en');
-    when(() => storage.readString(key: AppConst.modeKey)).thenReturn(null);
-    when(() => storage.readString(key: AppConst.colorKey)).thenReturn(null);
+    when(() => storage.readString(key: StorageKeys.tokenKey)).thenReturn(null);
+    when(() => storage.readString(key: StorageKeys.genderKey)).thenReturn(null);
+    when(() => storage.readString(key: StorageKeys.localeKey)).thenReturn('en');
+    when(() => storage.readString(key: StorageKeys.modeKey)).thenReturn(null);
+    when(() => storage.readString(key: StorageKeys.colorKey)).thenReturn(null);
 
     await tester.pumpApp(appService, themeService, authStorage, homeRepo);
     await tester.pumpAndSettle();