diff --git a/lib/application.dart b/lib/application.dart
index 478af5d..aec5b20 100644
--- a/lib/application.dart
+++ b/lib/application.dart
@@ -5,7 +5,9 @@ import 'package:lightmeter/data/ev_source/ev_source_type.dart';
 import 'package:lightmeter/data/permissions_service.dart';
 import 'package:lightmeter/screens/settings/settings_screen.dart';
 import 'package:provider/provider.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 
+import 'data/shared_prefs_service.dart';
 import 'generated/l10n.dart';
 import 'res/theme.dart';
 import 'screens/metering/flow_metering.dart';
@@ -38,35 +40,46 @@ class _ApplicationState extends State<Application> {
 
   @override
   Widget build(BuildContext context) {
-    return Provider.value(
-      value: widget.evSource,
-      child: Provider(
-        create: (context) => PermissionsService(),
-        child: StopTypeProvider(
-          child: MaterialApp(
-            theme: ThemeData(
-              useMaterial3: true,
-              colorScheme: lightColorScheme,
-            ),
-            localizationsDelegates: const [
-              S.delegate,
-              GlobalMaterialLocalizations.delegate,
-              GlobalWidgetsLocalizations.delegate,
-              GlobalCupertinoLocalizations.delegate,
+    return FutureBuilder<SharedPreferences>(
+      future: SharedPreferences.getInstance(),
+      builder: (context, snapshot) {
+        if (snapshot.data != null) {
+          return MultiProvider(
+            providers: [
+              Provider(create: (_) => UserPreferencesService(snapshot.data!)),
+              Provider.value(value: widget.evSource),
             ],
-            supportedLocales: S.delegate.supportedLocales,
-            builder: (context, child) => MediaQuery(
-              data: MediaQuery.of(context).copyWith(textScaleFactor: 1.0),
-              child: child!,
+            child: Provider(
+              create: (context) => PermissionsService(),
+              child: StopTypeProvider(
+                child: MaterialApp(
+                  theme: ThemeData(
+                    useMaterial3: true,
+                    colorScheme: lightColorScheme,
+                  ),
+                  localizationsDelegates: const [
+                    S.delegate,
+                    GlobalMaterialLocalizations.delegate,
+                    GlobalWidgetsLocalizations.delegate,
+                    GlobalCupertinoLocalizations.delegate,
+                  ],
+                  supportedLocales: S.delegate.supportedLocales,
+                  builder: (context, child) => MediaQuery(
+                    data: MediaQuery.of(context).copyWith(textScaleFactor: 1.0),
+                    child: child!,
+                  ),
+                  home: const MeteringFlow(),
+                  routes: {
+                    "metering": (context) => const MeteringFlow(),
+                    "settings": (context) => const SettingsScreen(),
+                  },
+                ),
+              ),
             ),
-            home: const MeteringFlow(),
-            routes: {
-              "metering": (context) => const MeteringFlow(),
-              "settings": (context) => const SettingsScreen(),
-            },
-          ),
-        ),
-      ),
+          );
+        }
+        return const SizedBox();
+      },
     );
   }
 }
diff --git a/lib/models/aperture_value.dart b/lib/data/models/aperture_value.dart
similarity index 100%
rename from lib/models/aperture_value.dart
rename to lib/data/models/aperture_value.dart
diff --git a/lib/models/exposure_pair.dart b/lib/data/models/exposure_pair.dart
similarity index 100%
rename from lib/models/exposure_pair.dart
rename to lib/data/models/exposure_pair.dart
diff --git a/lib/models/iso_value.dart b/lib/data/models/iso_value.dart
similarity index 100%
rename from lib/models/iso_value.dart
rename to lib/data/models/iso_value.dart
diff --git a/lib/models/nd_value.dart b/lib/data/models/nd_value.dart
similarity index 100%
rename from lib/models/nd_value.dart
rename to lib/data/models/nd_value.dart
diff --git a/lib/models/photography_value.dart b/lib/data/models/photography_value.dart
similarity index 100%
rename from lib/models/photography_value.dart
rename to lib/data/models/photography_value.dart
diff --git a/lib/models/shutter_speed_value.dart b/lib/data/models/shutter_speed_value.dart
similarity index 100%
rename from lib/models/shutter_speed_value.dart
rename to lib/data/models/shutter_speed_value.dart
diff --git a/lib/data/shared_prefs_service.dart b/lib/data/shared_prefs_service.dart
new file mode 100644
index 0000000..012c04e
--- /dev/null
+++ b/lib/data/shared_prefs_service.dart
@@ -0,0 +1,19 @@
+import 'package:lightmeter/data/models/nd_value.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import 'models/iso_value.dart';
+
+class UserPreferencesService {
+  static const _isoKey = "ISO";
+  static const _ndFilterKey = "ND";
+
+  final SharedPreferences _sharedPreferences;
+
+  UserPreferencesService(this._sharedPreferences);
+
+  IsoValue get iso => isoValues.firstWhere((v) => v.value == (_sharedPreferences.getInt(_isoKey) ?? 100));
+  set iso(IsoValue value) => _sharedPreferences.setInt(_isoKey, value.value);
+
+  NdValue get ndFilter => ndValues.firstWhere((v) => v.value == (_sharedPreferences.getInt(_ndFilterKey) ?? 0));
+  set ndFilter(NdValue value) => _sharedPreferences.setInt(_ndFilterKey, value.value);
+}
diff --git a/lib/screens/metering/bloc_metering.dart b/lib/screens/metering/bloc_metering.dart
index e54323a..c42b0a2 100644
--- a/lib/screens/metering/bloc_metering.dart
+++ b/lib/screens/metering/bloc_metering.dart
@@ -2,12 +2,11 @@ import 'dart:async';
 import 'dart:math';
 
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:lightmeter/models/aperture_value.dart';
-import 'package:lightmeter/models/exposure_pair.dart';
-import 'package:lightmeter/models/iso_value.dart';
-import 'package:lightmeter/models/nd_value.dart';
-import 'package:lightmeter/models/photography_value.dart';
-import 'package:lightmeter/models/shutter_speed_value.dart';
+import 'package:lightmeter/data/models/aperture_value.dart';
+import 'package:lightmeter/data/models/exposure_pair.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
+import 'package:lightmeter/data/models/shutter_speed_value.dart';
+import 'package:lightmeter/data/shared_prefs_service.dart';
 import 'package:lightmeter/screens/metering/communication/event_communication_metering.dart' as communication_events;
 import 'package:lightmeter/screens/metering/communication/state_communication_metering.dart' as communication_states;
 import 'package:lightmeter/utils/log_2.dart';
@@ -18,6 +17,7 @@ import 'state_metering.dart';
 
 class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
   final MeteringCommunicationBloc _communicationBloc;
+  final UserPreferencesService _userPreferencesService;
   late final StreamSubscription<communication_states.ScreenState> _communicationSubscription;
 
   List<ApertureValue> get _apertureValues => apertureValues.whereStopType(stopType);
@@ -25,13 +25,16 @@ class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
 
   StopType stopType;
 
-  MeteringBloc(this._communicationBloc, this.stopType)
-      : super(
+  MeteringBloc(
+    this._communicationBloc,
+    this._userPreferencesService,
+    this.stopType,
+  ) : super(
           MeteringState(
-            iso: isoValues.where((element) => element.value == 100).first,
+            iso: _userPreferencesService.iso,
             ev: 0.0,
             evCompensation: 0.0,
-            nd: ndValues.first,
+            nd: _userPreferencesService.ndFilter,
             exposurePairs: [],
           ),
         ) {
@@ -73,6 +76,7 @@ class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
   }
 
   void _onIsoChanged(IsoChangedEvent event, Emitter emit) {
+    _userPreferencesService.iso = event.isoValue;
     final ev = state.ev + log2(event.isoValue.value / state.iso.value);
     emit(MeteringState(
       iso: event.isoValue,
@@ -84,6 +88,7 @@ class MeteringBloc extends Bloc<MeteringEvent, MeteringState> {
   }
 
   void _onNdChanged(NdChangedEvent event, Emitter emit) {
+    _userPreferencesService.ndFilter = event.ndValue;
     final ev = state.ev - event.ndValue.stopReduction + state.nd.stopReduction;
     emit(MeteringState(
       iso: state.iso,
diff --git a/lib/screens/metering/components/exposure_pairs_list/components/exposure_pair_item.dart b/lib/screens/metering/components/exposure_pairs_list/components/exposure_pair_item.dart
index c31e3ce..d2747b8 100644
--- a/lib/screens/metering/components/exposure_pairs_list/components/exposure_pair_item.dart
+++ b/lib/screens/metering/components/exposure_pairs_list/components/exposure_pair_item.dart
@@ -1,5 +1,5 @@
 import 'package:flutter/material.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
 import 'package:lightmeter/res/dimens.dart';
 
 class ExposurePaitListItem<T extends PhotographyStopValue> extends StatelessWidget {
diff --git a/lib/screens/metering/components/exposure_pairs_list/exposure_pairs_list.dart b/lib/screens/metering/components/exposure_pairs_list/exposure_pairs_list.dart
index 2b66ccd..23dd10e 100644
--- a/lib/screens/metering/components/exposure_pairs_list/exposure_pairs_list.dart
+++ b/lib/screens/metering/components/exposure_pairs_list/exposure_pairs_list.dart
@@ -1,5 +1,5 @@
 import 'package:flutter/material.dart';
-import 'package:lightmeter/models/exposure_pair.dart';
+import 'package:lightmeter/data/models/exposure_pair.dart';
 import 'package:lightmeter/res/dimens.dart';
 import 'package:lightmeter/screens/metering/components/exposure_pairs_list/components/exposure_pair_item.dart';
 
diff --git a/lib/screens/metering/components/topbar/components/dialog_picker.dart b/lib/screens/metering/components/topbar/components/dialog_picker.dart
index 7b41e0a..6f80e60 100644
--- a/lib/screens/metering/components/topbar/components/dialog_picker.dart
+++ b/lib/screens/metering/components/topbar/components/dialog_picker.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:lightmeter/generated/l10n.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
 import 'package:lightmeter/res/dimens.dart';
 
 typedef DialogPickerItemBuilder<T extends PhotographyValue> = Widget Function(BuildContext, T);
diff --git a/lib/screens/metering/components/topbar/topbar.dart b/lib/screens/metering/components/topbar/topbar.dart
index 8bbfe9d..506dd08 100644
--- a/lib/screens/metering/components/topbar/topbar.dart
+++ b/lib/screens/metering/components/topbar/topbar.dart
@@ -2,10 +2,10 @@ import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:lightmeter/data/ev_source/camera/bloc_camera.dart';
 import 'package:lightmeter/generated/l10n.dart';
-import 'package:lightmeter/models/exposure_pair.dart';
-import 'package:lightmeter/models/iso_value.dart';
-import 'package:lightmeter/models/nd_value.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/exposure_pair.dart';
+import 'package:lightmeter/data/models/iso_value.dart';
+import 'package:lightmeter/data/models/nd_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
 import 'package:lightmeter/res/dimens.dart';
 
 import 'components/camera_preview.dart';
diff --git a/lib/screens/metering/event_metering.dart b/lib/screens/metering/event_metering.dart
index 275f03d..302aff2 100644
--- a/lib/screens/metering/event_metering.dart
+++ b/lib/screens/metering/event_metering.dart
@@ -1,6 +1,6 @@
-import 'package:lightmeter/models/iso_value.dart';
-import 'package:lightmeter/models/nd_value.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/iso_value.dart';
+import 'package:lightmeter/data/models/nd_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
 
 abstract class MeteringEvent {
   const MeteringEvent();
diff --git a/lib/screens/metering/flow_metering.dart b/lib/screens/metering/flow_metering.dart
index 1fe20f0..6274c10 100644
--- a/lib/screens/metering/flow_metering.dart
+++ b/lib/screens/metering/flow_metering.dart
@@ -3,7 +3,8 @@ import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:lightmeter/data/ev_source/camera/bloc_camera.dart';
 import 'package:lightmeter/data/ev_source/ev_source_type.dart';
 import 'package:lightmeter/data/ev_source/random_ev/bloc_random_ev.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
+import 'package:lightmeter/data/shared_prefs_service.dart';
 import 'package:lightmeter/screens/metering/bloc_metering.dart';
 import 'package:lightmeter/screens/metering/communication/bloc_communication_metering.dart';
 
@@ -20,6 +21,7 @@ class MeteringFlow extends StatelessWidget {
         BlocProvider(
           create: (context) => MeteringBloc(
             context.read<MeteringCommunicationBloc>(),
+            context.read<UserPreferencesService>(),
             context.read<StopType>(),
           ),
         ),
diff --git a/lib/screens/metering/screen_metering.dart b/lib/screens/metering/screen_metering.dart
index 480dba0..9dc44a6 100644
--- a/lib/screens/metering/screen_metering.dart
+++ b/lib/screens/metering/screen_metering.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
 import 'package:lightmeter/res/dimens.dart';
 import 'package:lightmeter/screens/settings/settings_screen.dart';
 
diff --git a/lib/screens/metering/state_metering.dart b/lib/screens/metering/state_metering.dart
index f6dbb17..b18016c 100644
--- a/lib/screens/metering/state_metering.dart
+++ b/lib/screens/metering/state_metering.dart
@@ -1,6 +1,6 @@
-import 'package:lightmeter/models/exposure_pair.dart';
-import 'package:lightmeter/models/iso_value.dart';
-import 'package:lightmeter/models/nd_value.dart';
+import 'package:lightmeter/data/models/exposure_pair.dart';
+import 'package:lightmeter/data/models/iso_value.dart';
+import 'package:lightmeter/data/models/nd_value.dart';
 
 class MeteringState {
   final double ev;
diff --git a/lib/screens/settings/components/fractional_stops/dialog_fractional_stops.dart b/lib/screens/settings/components/fractional_stops/dialog_fractional_stops.dart
index 40b9a4a..2c4514b 100644
--- a/lib/screens/settings/components/fractional_stops/dialog_fractional_stops.dart
+++ b/lib/screens/settings/components/fractional_stops/dialog_fractional_stops.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:lightmeter/generated/l10n.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
 
 class FractionalStopsDialog extends StatefulWidget {
   final StopType selectedType;
diff --git a/lib/screens/settings/components/fractional_stops/list_tile_fractional_stops.dart b/lib/screens/settings/components/fractional_stops/list_tile_fractional_stops.dart
index dac28af..5f75f0c 100644
--- a/lib/screens/settings/components/fractional_stops/list_tile_fractional_stops.dart
+++ b/lib/screens/settings/components/fractional_stops/list_tile_fractional_stops.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:lightmeter/generated/l10n.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
 import 'package:lightmeter/utils/stop_type_provider.dart';
 import 'package:provider/provider.dart';
 
diff --git a/lib/utils/stop_type_provider.dart b/lib/utils/stop_type_provider.dart
index ae9f041..8a6b619 100644
--- a/lib/utils/stop_type_provider.dart
+++ b/lib/utils/stop_type_provider.dart
@@ -1,5 +1,5 @@
 import 'package:flutter/material.dart';
-import 'package:lightmeter/models/photography_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
 import 'package:provider/provider.dart';
 
 class StopTypeProvider extends StatefulWidget {
diff --git a/pubspec.yaml b/pubspec.yaml
index c9d5f79..fa6bb99 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -19,6 +19,7 @@ dependencies:
   material_color_utilities: ^0.2.0
   permission_handler: 10.2.0
   provider: ^6.0.4
+  shared_preferences: 2.0.15
 
 dev_dependencies:
   google_fonts: ^3.0.1
diff --git a/test/photograpy_values_test.dart b/test/photograpy_values_test.dart
index 7af90b9..b3bd4eb 100644
--- a/test/photograpy_values_test.dart
+++ b/test/photograpy_values_test.dart
@@ -1,7 +1,7 @@
-import 'package:lightmeter/models/aperture_value.dart';
-import 'package:lightmeter/models/iso_value.dart';
-import 'package:lightmeter/models/photography_value.dart';
-import 'package:lightmeter/models/shutter_speed_value.dart';
+import 'package:lightmeter/data/models/aperture_value.dart';
+import 'package:lightmeter/data/models/iso_value.dart';
+import 'package:lightmeter/data/models/photography_value.dart';
+import 'package:lightmeter/data/models/shutter_speed_value.dart';
 import 'package:test/test.dart';
 
 void main() {