diff --git a/app/lib/entity/pref/provider/shared_preferences.dart b/app/lib/entity/pref/provider/shared_preferences.dart
index ceb665bd..1a439715 100644
--- a/app/lib/entity/pref/provider/shared_preferences.dart
+++ b/app/lib/entity/pref/provider/shared_preferences.dart
@@ -1,8 +1,7 @@
 import 'package:nc_photos/entity/pref.dart';
-import 'package:nc_photos/mobile/platform.dart'
-    if (dart.library.html) 'package:nc_photos/web/platform.dart' as platform;
 import 'package:nc_photos/use_case/compat/v34.dart';
 import 'package:np_common/type.dart';
+import 'package:np_universal_storage/np_universal_storage.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import 'package:shared_preferences_platform_interface/shared_preferences_platform_interface.dart';
 
@@ -14,7 +13,7 @@ class PrefSharedPreferencesProvider extends PrefProvider {
     //   await CompatV32.migratePref();
     // }
     if (await CompatV34.isPrefNeedMigration()) {
-      await CompatV34.migratePref(platform.UniversalStorage());
+      await CompatV34.migratePref(UniversalStorage());
     }
     return SharedPreferences.getInstance().then((pref) {
       _pref = pref;
diff --git a/app/lib/entity/pref/provider/universal_storage.dart b/app/lib/entity/pref/provider/universal_storage.dart
index eb4785e7..8e57966b 100644
--- a/app/lib/entity/pref/provider/universal_storage.dart
+++ b/app/lib/entity/pref/provider/universal_storage.dart
@@ -1,16 +1,15 @@
 import 'dart:convert';
 
 import 'package:nc_photos/entity/pref.dart';
-import 'package:nc_photos/mobile/platform.dart'
-    if (dart.library.html) 'package:nc_photos/web/platform.dart' as platform;
 import 'package:np_common/type.dart';
+import 'package:np_universal_storage/np_universal_storage.dart';
 
 /// [Pref] backed by [UniversalStorage]
 class PrefUniversalStorageProvider extends PrefProvider {
   PrefUniversalStorageProvider(this.name);
 
   Future<void> init() async {
-    final prefStr = await platform.UniversalStorage().getString(name) ?? "{}";
+    final prefStr = await UniversalStorage().getString(name) ?? "{}";
     _data
       ..clear()
       ..addAll(jsonDecode(prefStr));
@@ -41,14 +40,14 @@ class PrefUniversalStorageProvider extends PrefProvider {
   @override
   Future<bool> remove(PrefKeyInterface key) async {
     final newData = Map.of(_data)..remove(key.toStringKey());
-    await platform.UniversalStorage().putString(name, jsonEncode(newData));
+    await UniversalStorage().putString(name, jsonEncode(newData));
     _data.remove(key.toStringKey());
     return true;
   }
 
   @override
   Future<bool> clear() async {
-    await platform.UniversalStorage().remove(name);
+    await UniversalStorage().remove(name);
     _data.clear();
     return true;
   }
@@ -61,7 +60,7 @@ class PrefUniversalStorageProvider extends PrefProvider {
   Future<bool> _set<T>(PrefKeyInterface key, T value) async {
     final newData = Map.of(_data)
       ..addEntries([MapEntry(key.toStringKey(), value)]);
-    await platform.UniversalStorage().putString(name, jsonEncode(newData));
+    await UniversalStorage().putString(name, jsonEncode(newData));
     _data[key.toStringKey()] = value;
     return true;
   }
diff --git a/app/lib/mobile/platform.dart b/app/lib/mobile/platform.dart
index 07b05654..a7be646c 100644
--- a/app/lib/mobile/platform.dart
+++ b/app/lib/mobile/platform.dart
@@ -3,4 +3,3 @@ export 'download.dart';
 export 'file_saver.dart';
 export 'google_gps_map.dart';
 export 'notification.dart';
-export 'universal_storage.dart';
diff --git a/app/lib/touch_manager.dart b/app/lib/touch_manager.dart
index f687e0aa..2f2830ef 100644
--- a/app/lib/touch_manager.dart
+++ b/app/lib/touch_manager.dart
@@ -6,14 +6,13 @@ import 'package:nc_photos/di_container.dart';
 import 'package:nc_photos/entity/file.dart';
 import 'package:nc_photos/entity/file_descriptor.dart';
 import 'package:nc_photos/exception.dart';
-import 'package:nc_photos/mobile/platform.dart'
-    if (dart.library.html) 'package:nc_photos/web/platform.dart' as platform;
 import 'package:nc_photos/remote_storage_util.dart' as remote_storage_util;
 import 'package:nc_photos/throttler.dart';
 import 'package:nc_photos/use_case/ls_single_file.dart';
 import 'package:nc_photos/use_case/put_file_binary.dart';
 import 'package:np_codegen/np_codegen.dart';
 import 'package:np_common/or_null.dart';
+import 'package:np_universal_storage/np_universal_storage.dart';
 import 'package:path/path.dart' as path_lib;
 import 'package:uuid/uuid.dart';
 
@@ -116,10 +115,10 @@ class TouchManager {
   Future<void> setLocalEtag(Account account, File dir, String? etag) {
     final name = _getLocalStorageName(account, dir);
     if (etag == null) {
-      return platform.UniversalStorage().remove(name);
+      return UniversalStorage().remove(name);
     } else {
       _log.info("[setLocalEtag] Set local etag for file '${dir.path}': $etag");
-      return platform.UniversalStorage().putString(name, etag);
+      return UniversalStorage().putString(name, etag);
     }
   }
 
@@ -175,7 +174,7 @@ class TouchManager {
 
   Future<String?> _getLocalEtag(Account account, File file) async {
     final name = _getLocalStorageName(account, file);
-    return platform.UniversalStorage().getString(name);
+    return UniversalStorage().getString(name);
   }
 
   String _getLocalStorageName(Account account, File file) {
diff --git a/app/lib/use_case/compat/v34.dart b/app/lib/use_case/compat/v34.dart
index 0cbb854c..454fd320 100644
--- a/app/lib/use_case/compat/v34.dart
+++ b/app/lib/use_case/compat/v34.dart
@@ -2,9 +2,9 @@ import 'dart:convert';
 
 import 'package:logging/logging.dart';
 import 'package:nc_photos/account.dart';
-import 'package:nc_photos/platform/universal_storage.dart';
 import 'package:np_codegen/np_codegen.dart';
 import 'package:np_common/type.dart';
+import 'package:np_universal_storage/np_universal_storage.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
 part 'v34.g.dart';
@@ -39,7 +39,8 @@ class CompatV34 {
       final id = Account.newId();
       account2["account"]["id"] = id;
       newJsons.add(account2["account"]);
-      await storage.putString("accounts/$id/pref", jsonEncode(account2["settings"]));
+      await storage.putString(
+          "accounts/$id/pref", jsonEncode(account2["settings"]));
     }
     if (await pref.setStringList(
         "accounts3", newJsons.map((e) => jsonEncode(e)).toList())) {
diff --git a/app/lib/web/platform.dart b/app/lib/web/platform.dart
index 07b05654..a7be646c 100644
--- a/app/lib/web/platform.dart
+++ b/app/lib/web/platform.dart
@@ -3,4 +3,3 @@ export 'download.dart';
 export 'file_saver.dart';
 export 'google_gps_map.dart';
 export 'notification.dart';
-export 'universal_storage.dart';
diff --git a/app/pubspec.lock b/app/pubspec.lock
index 22ae786f..f5e5563b 100644
--- a/app/pubspec.lock
+++ b/app/pubspec.lock
@@ -1039,6 +1039,13 @@ packages:
       relative: true
     source: path
     version: "0.0.1"
+  np_universal_storage:
+    dependency: "direct main"
+    description:
+      path: "../np_universal_storage"
+      relative: true
+    source: path
+    version: "0.0.1"
   octo_image:
     dependency: "direct main"
     description:
diff --git a/app/pubspec.yaml b/app/pubspec.yaml
index 87133471..379405a4 100644
--- a/app/pubspec.yaml
+++ b/app/pubspec.yaml
@@ -117,6 +117,8 @@ dependencies:
     path: ../np_string
   np_ui:
     path: ../np_ui
+  np_universal_storage:
+    path: ../np_universal_storage
   octo_image: any
   page_view_indicators: ^2.0.0
   path: ^1.8.0
diff --git a/app/test/use_case/compat/v34_test.dart b/app/test/use_case/compat/v34_test.dart
index c655f8ff..6b77307e 100644
--- a/app/test/use_case/compat/v34_test.dart
+++ b/app/test/use_case/compat/v34_test.dart
@@ -1,7 +1,7 @@
 import 'dart:convert';
 
-import 'package:nc_photos/platform/universal_storage.dart';
 import 'package:nc_photos/use_case/compat/v34.dart';
+import 'package:np_universal_storage/np_universal_storage.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import 'package:test/test.dart';
 
diff --git a/np_universal_storage/.gitignore b/np_universal_storage/.gitignore
new file mode 100644
index 00000000..96486fd9
--- /dev/null
+++ b/np_universal_storage/.gitignore
@@ -0,0 +1,30 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+migrate_working_dir/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# The .vscode folder contains launch configuration and tasks you configure in
+# VS Code which you may wish to be included in version control, so this line
+# is commented out by default.
+#.vscode/
+
+# Flutter/Dart/Pub related
+# Libraries should not include pubspec.lock, per https://dart.dev/guides/libraries/private-files#pubspeclock.
+/pubspec.lock
+**/doc/api/
+.dart_tool/
+.packages
+build/
diff --git a/np_universal_storage/.metadata b/np_universal_storage/.metadata
new file mode 100644
index 00000000..788b91db
--- /dev/null
+++ b/np_universal_storage/.metadata
@@ -0,0 +1,10 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: 4d9e56e694b656610ab87fcf2efbcd226e0ed8cf
+  channel: stable
+
+project_type: package
diff --git a/np_universal_storage/analysis_options.yaml b/np_universal_storage/analysis_options.yaml
new file mode 100644
index 00000000..f92d2567
--- /dev/null
+++ b/np_universal_storage/analysis_options.yaml
@@ -0,0 +1 @@
+include: package:np_lints/np.yaml
diff --git a/np_universal_storage/lib/np_universal_storage.dart b/np_universal_storage/lib/np_universal_storage.dart
new file mode 100644
index 00000000..d8874f98
--- /dev/null
+++ b/np_universal_storage/lib/np_universal_storage.dart
@@ -0,0 +1,4 @@
+library np_universal_storage;
+
+export 'src/memory_storage.dart';
+export 'src/universal_storage.dart';
diff --git a/np_universal_storage/lib/src/memory_storage.dart b/np_universal_storage/lib/src/memory_storage.dart
new file mode 100644
index 00000000..46820448
--- /dev/null
+++ b/np_universal_storage/lib/src/memory_storage.dart
@@ -0,0 +1,29 @@
+import 'package:flutter/foundation.dart';
+import 'package:np_universal_storage/src/universal_storage.dart';
+
+/// UniversalStorage backed by memory, useful in unit tests
+@visibleForTesting
+class UniversalMemoryStorage implements UniversalStorage {
+  @override
+  Future<void> putBinary(String name, Uint8List content) async {
+    data[name] = content;
+  }
+
+  @override
+  Future<Uint8List?> getBinary(String name) async => data[name];
+
+  @override
+  Future<void> putString(String name, String content) async {
+    data[name] = content;
+  }
+
+  @override
+  Future<String?> getString(String name) async => data[name];
+
+  @override
+  Future<void> remove(String name) async {
+    data.remove(name);
+  }
+
+  final data = <String, dynamic>{};
+}
diff --git a/app/lib/mobile/universal_storage.dart b/np_universal_storage/lib/src/native/universal_storage.dart
similarity index 81%
rename from app/lib/mobile/universal_storage.dart
rename to np_universal_storage/lib/src/native/universal_storage.dart
index d52fd075..469ed2f3 100644
--- a/app/lib/mobile/universal_storage.dart
+++ b/np_universal_storage/lib/src/native/universal_storage.dart
@@ -1,21 +1,21 @@
 import 'dart:io';
 import 'dart:typed_data';
 
-import 'package:nc_photos/platform/universal_storage.dart' as itf;
 import 'package:np_string/np_string.dart';
+import 'package:np_universal_storage/src/universal_storage.dart' as itf;
 import 'package:path/path.dart' as path_lib;
 import 'package:path_provider/path_provider.dart';
 
-class UniversalStorage extends itf.UniversalStorage {
+class UniversalStorage implements itf.UniversalStorage {
   @override
-  putBinary(String name, Uint8List content) async {
+  Future<void> putBinary(String name, Uint8List content) async {
     final storageDir = await _openStorageDirForFile(name);
     final file = File("${storageDir.path}/$name");
     await file.writeAsBytes(content, flush: true);
   }
 
   @override
-  getBinary(String name) async {
+  Future<Uint8List?> getBinary(String name) async {
     final storageDir = await _openStorageDirForFile(name);
     final file = File("${storageDir.path}/$name");
     if (await file.exists()) {
@@ -26,14 +26,14 @@ class UniversalStorage extends itf.UniversalStorage {
   }
 
   @override
-  putString(String name, String content) async {
+  Future<void> putString(String name, String content) async {
     final storageDir = await _openStorageDirForFile(name);
     final file = File("${storageDir.path}/$name");
     await file.writeAsString(content, flush: true);
   }
 
   @override
-  getString(String name) async {
+  Future<String?> getString(String name) async {
     final storageDir = await _openStorageDirForFile(name);
     final file = File("${storageDir.path}/$name");
     if (await file.exists()) {
@@ -44,7 +44,7 @@ class UniversalStorage extends itf.UniversalStorage {
   }
 
   @override
-  remove(String name) async {
+  Future<void> remove(String name) async {
     final storageDir = await _openStorageDirForFile(name);
     final file = File("${storageDir.path}/$name");
     if (await file.exists()) {
diff --git a/app/lib/platform/universal_storage.dart b/np_universal_storage/lib/src/universal_storage.dart
similarity index 51%
rename from app/lib/platform/universal_storage.dart
rename to np_universal_storage/lib/src/universal_storage.dart
index 4bcd7bdc..56153825 100644
--- a/app/lib/platform/universal_storage.dart
+++ b/np_universal_storage/lib/src/universal_storage.dart
@@ -1,10 +1,16 @@
-import 'package:flutter/foundation.dart';
+import 'dart:typed_data';
+
+import 'package:np_universal_storage/src/native/universal_storage.dart'
+    if (dart.library.html) 'package:np_universal_storage/src/web/universal_storage.dart'
+    as impl;
 
 /// Store simple contents across different platforms
 ///
 /// On mobile, the contents will be persisted as a file. On web, the contents
 /// will be stored in local storage
 abstract class UniversalStorage {
+  factory UniversalStorage() => impl.UniversalStorage();
+
   Future<void> putBinary(String name, Uint8List content);
 
   /// Return the content associated with [name], or null if no such association
@@ -19,30 +25,3 @@ abstract class UniversalStorage {
 
   Future<void> remove(String name);
 }
-
-/// UniversalStorage backed by memory, useful in unit tests
-@visibleForTesting
-class UniversalMemoryStorage implements UniversalStorage {
-  @override
-  putBinary(String name, Uint8List content) async {
-    data[name] = content;
-  }
-
-  @override
-  getBinary(String name) async => data[name];
-
-  @override
-  putString(String name, String content) async {
-    data[name] = content;
-  }
-
-  @override
-  getString(String name) async => data[name];
-
-  @override
-  remove(String name) async {
-    data.remove(name);
-  }
-
-  final data = <String, dynamic>{};
-}
diff --git a/app/lib/web/universal_storage.dart b/np_universal_storage/lib/src/web/universal_storage.dart
similarity index 72%
rename from app/lib/web/universal_storage.dart
rename to np_universal_storage/lib/src/web/universal_storage.dart
index 3856a340..5d7d6958 100644
--- a/app/lib/web/universal_storage.dart
+++ b/np_universal_storage/lib/src/web/universal_storage.dart
@@ -1,14 +1,14 @@
 import 'dart:convert';
 import 'dart:typed_data';
 
-import 'package:nc_photos/platform/universal_storage.dart' as itf;
+import 'package:np_universal_storage/src/universal_storage.dart' as itf;
 import 'package:shared_preferences/shared_preferences.dart';
 
 const String _prefix = "_universal_storage";
 
-class UniversalStorage extends itf.UniversalStorage {
+class UniversalStorage implements itf.UniversalStorage {
   @override
-  putBinary(String name, Uint8List content) async {
+  Future<void> putBinary(String name, Uint8List content) async {
     // SharedPreferences happens to save to local storage on web, we'll just use
     // that
     final pref = await SharedPreferences.getInstance();
@@ -16,7 +16,7 @@ class UniversalStorage extends itf.UniversalStorage {
   }
 
   @override
-  getBinary(String name) async {
+  Future<Uint8List?> getBinary(String name) async {
     final pref = await SharedPreferences.getInstance();
     final contentStr = pref.getString("$_prefix.$name");
     if (contentStr == null) {
@@ -27,7 +27,7 @@ class UniversalStorage extends itf.UniversalStorage {
   }
 
   @override
-  putString(String name, String content) async {
+  Future<void> putString(String name, String content) async {
     // SharedPreferences happens to save to local storage on web, we'll just use
     // that
     final pref = await SharedPreferences.getInstance();
@@ -35,13 +35,13 @@ class UniversalStorage extends itf.UniversalStorage {
   }
 
   @override
-  getString(String name) async {
+  Future<String?> getString(String name) async {
     final pref = await SharedPreferences.getInstance();
     return pref.getString("$_prefix.$name");
   }
 
   @override
-  remove(String name) async {
+  Future<void> remove(String name) async {
     final pref = await SharedPreferences.getInstance();
     await pref.remove("$_prefix.$name");
   }
diff --git a/np_universal_storage/pubspec.yaml b/np_universal_storage/pubspec.yaml
new file mode 100644
index 00000000..abf83442
--- /dev/null
+++ b/np_universal_storage/pubspec.yaml
@@ -0,0 +1,22 @@
+name: np_universal_storage
+description: A new Flutter package project.
+version: 0.0.1
+homepage:
+publish_to: none
+
+environment:
+  sdk: '>=2.19.6 <3.0.0'
+  flutter: ">=3.3.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+  np_string:
+    path: ../np_string
+  path: ^1.8.0
+  path_provider: ^2.0.15
+  shared_preferences: ^2.0.8
+
+dev_dependencies:
+  np_lints:
+    path: ../np_lints