diff --git a/mobile/ios/Runner/Sync/MessagesImpl.swift b/mobile/ios/Runner/Sync/MessagesImpl.swift
index ddfd023690..181b343c6e 100644
--- a/mobile/ios/Runner/Sync/MessagesImpl.swift
+++ b/mobile/ios/Runner/Sync/MessagesImpl.swift
@@ -144,7 +144,7 @@ class NativeSyncApiImpl: ImmichPlugin, NativeSyncApi, FlutterPlugin {
   
   private func getMediaChanges() throws -> SyncDelta {
     guard #available(iOS 16, *) else {
-      throw PigeonError(code: "UNSUPPORTED_OS", message: "This feature requires iOS 16 or later.", details: nil)
+      throw PigeonError(code: kUnSupportedOSError, message: "This feature requires iOS 16 or later.", details: nil)
     }
     
     guard PHPhotoLibrary.authorizationStatus(for: .readWrite) == .authorized else {
@@ -437,7 +437,7 @@ class NativeSyncApiImpl: ImmichPlugin, NativeSyncApi, FlutterPlugin {
   }
   
   func getTrashedAssets() throws -> [String: [PlatformAsset]] {
-    throw PigeonError(code: "UNSUPPORTED_OS", message: "This feature not supported on iOS.", details: nil)
+    throw PigeonError(code: kUnSupportedOSError, message: "This feature not supported on iOS.", details: nil)
   }
 
   func restoreFromTrashById(mediaId: String, type: Int64, completion: @escaping (Result<Bool, Error>) -> Void) {
@@ -453,11 +453,33 @@ class NativeSyncApiImpl: ImmichPlugin, NativeSyncApi, FlutterPlugin {
     }
   }
   
+
+  private func cloudIdError(for error: Error) -> (kind: CloudIdErrorKind, message: String) {
+    let nsError = error as NSError
+    var message = "Error getting Cloud Id: \(error.localizedDescription)"
+
+    guard nsError.domain == PHPhotosErrorDomain else {
+      return (.unknown, message)
+    }
+
+    switch nsError.code {
+    case PHPhotosError.identifierNotFound.rawValue:
+      return (.notFound, message)
+    case PHPhotosError.multipleIdentifiersFound.rawValue:
+      if let matches = nsError.userInfo[PHLocalIdentifiersErrorKey] as? [String] {
+        message += " (matched: \(matches.joined(separator: ", ")))"
+      }
+      return (.ambiguous, message)
+    default:
+      return (.unknown, message)
+    }
+  }
+
   func getCloudIdForAssetIds(assetIds: [String]) throws -> [CloudIdResult] {
     guard #available(iOS 16, *) else {
-      return assetIds.map { CloudIdResult(assetId: $0) }
+      throw PigeonError(code: kUnSupportedOSError, message: "This feature requires iOS 16 or later.", details: nil)
     }
-    
+
     var mappings: [CloudIdResult] = []
     let result = PHPhotoLibrary.shared().cloudIdentifierMappings(forLocalIdentifiers: assetIds)
     for (key, value) in result {
@@ -468,10 +490,12 @@ class NativeSyncApiImpl: ImmichPlugin, NativeSyncApi, FlutterPlugin {
         if !cloudId.hasSuffix(":") {
           mappings.append(CloudIdResult(assetId: key, cloudId: cloudId))
         } else {
-          mappings.append(CloudIdResult(assetId: key, error: "Incomplete Cloud Id: \(cloudId)"))
+          mappings.append(
+            CloudIdResult(assetId: key, error: "Incomplete Cloud Id: \(cloudId)", errorKind: .incomplete))
         }
       case .failure(let error):
-        mappings.append(CloudIdResult(assetId: key, error: "Error getting Cloud Id: \(error.localizedDescription)"))
+        let (kind, message) = cloudIdError(for: error)
+        mappings.append(CloudIdResult(assetId: key, error: message, errorKind: kind))
       }
     }
     return mappings;
diff --git a/mobile/lib/domain/models/asset/asset_metadata.model.dart b/mobile/lib/domain/models/asset/asset_metadata.model.dart
index fc29da3db0..ad326da249 100644
--- a/mobile/lib/domain/models/asset/asset_metadata.model.dart
+++ b/mobile/lib/domain/models/asset/asset_metadata.model.dart
@@ -1,3 +1,7 @@
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+part 'asset_metadata.model.freezed.dart';
+
 enum RemoteAssetMetadataKey {
   mobileApp("mobile-app");
 
@@ -23,40 +27,24 @@ class RemoteAssetMetadataItem {
   }
 }
 
-class RemoteAssetMobileAppMetadata extends RemoteAssetMetadataValue {
-  final String? cloudId;
-  final String? createdAt;
-  final String? adjustmentTime;
-  final String? latitude;
-  final String? longitude;
+@freezed
+abstract class RemoteAssetMobileAppMetadata extends RemoteAssetMetadataValue with _$RemoteAssetMobileAppMetadata {
+  const factory RemoteAssetMobileAppMetadata({
+    String? cloudId,
+    String? createdAt,
+    String? adjustmentTime,
+    String? latitude,
+    String? longitude,
+  }) = _RemoteAssetMobileAppMetadata;
 
-  const RemoteAssetMobileAppMetadata({
-    this.cloudId,
-    this.createdAt,
-    this.adjustmentTime,
-    this.latitude,
-    this.longitude,
-  });
+  const RemoteAssetMobileAppMetadata._();
 
   @override
-  Map<String, dynamic> toJson() {
-    final map = <String, Object?>{};
-    if (cloudId != null) {
-      map["iCloudId"] = cloudId;
-    }
-    if (createdAt != null) {
-      map["createdAt"] = createdAt;
-    }
-    if (adjustmentTime != null) {
-      map["adjustmentTime"] = adjustmentTime;
-    }
-    if (latitude != null) {
-      map["latitude"] = latitude;
-    }
-    if (longitude != null) {
-      map["longitude"] = longitude;
-    }
-
-    return map;
-  }
+  Map<String, dynamic> toJson() => {
+    'iCloudId': ?cloudId,
+    'createdAt': ?createdAt,
+    'adjustmentTime': ?adjustmentTime,
+    'latitude': ?latitude,
+    'longitude': ?longitude,
+  };
 }
diff --git a/mobile/lib/domain/services/background_worker.service.dart b/mobile/lib/domain/services/background_worker.service.dart
index 8161df5c51..b902f0f0f4 100644
--- a/mobile/lib/domain/services/background_worker.service.dart
+++ b/mobile/lib/domain/services/background_worker.service.dart
@@ -78,7 +78,6 @@ class BackgroundWorkerBgService extends BackgroundWorkerFlutterApi {
     _ref = ref;
     _localSyncService = LocalSyncService(
       localAlbumRepository: ref.read(localAlbumRepository),
-      localAssetRepository: ref.read(localAssetRepository),
       nativeSyncApi: ref.read(nativeSyncApiProvider),
       trashedLocalAssetRepository: ref.read(trashedLocalAssetRepository),
       assetMediaRepository: ref.read(assetMediaRepositoryProvider),
diff --git a/mobile/lib/domain/services/hash.service.dart b/mobile/lib/domain/services/hash.service.dart
index 8a573ee209..a6f87ae30d 100644
--- a/mobile/lib/domain/services/hash.service.dart
+++ b/mobile/lib/domain/services/hash.service.dart
@@ -42,7 +42,7 @@ class HashService {
     final Stopwatch stopwatch = Stopwatch()..start();
     try {
       // Migrate hashes from cloud ID to local ID so we don't have to re-hash them
-      // await _localAssetRepository.reconcileHashesFromCloudId();
+      await _localAssetRepository.reconcileHashesFromCloudId();
 
       // Sorted by backupSelection followed by isCloud
       final localAlbums = await _localAlbumRepository.getBackupAlbums();
diff --git a/mobile/lib/domain/services/local_sync.service.dart b/mobile/lib/domain/services/local_sync.service.dart
index 9e272ac65f..250015acda 100644
--- a/mobile/lib/domain/services/local_sync.service.dart
+++ b/mobile/lib/domain/services/local_sync.service.dart
@@ -6,10 +6,10 @@ import 'package:flutter/services.dart';
 import 'package:immich_mobile/domain/models/album/local_album.model.dart';
 import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
 import 'package:immich_mobile/domain/models/store.model.dart';
+import 'package:immich_mobile/domain/utils/cloud_id_resolver.dart';
 import 'package:immich_mobile/entities/store.entity.dart';
 import 'package:immich_mobile/extensions/platform_extensions.dart';
 import 'package:immich_mobile/infrastructure/repositories/local_album.repository.dart';
-import 'package:immich_mobile/infrastructure/repositories/local_asset.repository.dart';
 import 'package:immich_mobile/infrastructure/repositories/trashed_local_asset.repository.dart';
 import 'package:immich_mobile/platform/native_sync_api.g.dart';
 import 'package:immich_mobile/repositories/asset_media.repository.dart';
@@ -22,8 +22,6 @@ const String _kSyncCancelledCode = "SYNC_CANCELLED";
 
 class LocalSyncService {
   final DriftLocalAlbumRepository _localAlbumRepository;
-  // ignore: unused_field
-  final DriftLocalAssetRepository _localAssetRepository;
   final NativeSyncApi _nativeSyncApi;
   final DriftTrashedLocalAssetRepository _trashedLocalAssetRepository;
   final AssetMediaRepository _assetMediaRepository;
@@ -33,7 +31,6 @@ class LocalSyncService {
 
   LocalSyncService({
     required this._localAlbumRepository,
-    required this._localAssetRepository,
     required this._nativeSyncApi,
     required this._trashedLocalAssetRepository,
     required this._assetMediaRepository,
@@ -57,11 +54,6 @@ class LocalSyncService {
         }
       }
 
-      if (CurrentPlatform.isIOS) {
-        // final assets = await _localAssetRepository.getEmptyCloudIdAssets();
-        // await _mapIosCloudIds(assets);
-      }
-
       if (full || await _nativeSyncApi.shouldFullSync()) {
         _log.fine("Full sync request from ${full ? "user" : "native"}");
         return await fullSync();
@@ -116,7 +108,7 @@ class LocalSyncService {
           await updateAlbum(dbAlbum, album);
         }
 
-        await _mapIosCloudIds(newAssets);
+        await _mapCloudIds(newAssets);
       }
       await _nativeSyncApi.checkpointSync();
     } on PlatformException catch (e, s) {
@@ -175,7 +167,7 @@ class LocalSyncService {
           : <LocalAsset>[];
 
       await _localAlbumRepository.upsert(album, toUpsert: assets);
-      await _mapIosCloudIds(assets);
+      await _mapCloudIds(assets);
       _log.fine("Successfully added device album ${album.name}");
     } catch (e, s) {
       _log.warning("Error while adding device album", e, s);
@@ -257,7 +249,7 @@ class LocalSyncService {
         toUpsert: newAssets,
       );
 
-      await _mapIosCloudIds(newAssets);
+      await _mapCloudIds(newAssets);
       return true;
     } catch (e, s) {
       _log.warning("Error on fast syncing local album: ${dbAlbum.name}", e, s);
@@ -289,7 +281,7 @@ class LocalSyncService {
       if (dbAlbum.assetCount == 0) {
         _log.fine("Device album ${deviceAlbum.name} is empty. Adding assets to DB.");
         await _localAlbumRepository.upsert(updatedDeviceAlbum, toUpsert: assetsInDevice);
-        await _mapIosCloudIds(assetsInDevice);
+        await _mapCloudIds(assetsInDevice);
         return true;
       }
 
@@ -327,7 +319,7 @@ class LocalSyncService {
       }
 
       await _localAlbumRepository.upsert(updatedDeviceAlbum, toUpsert: assetsToUpsert, toDelete: assetsToDelete);
-      await _mapIosCloudIds(assetsToUpsert);
+      await _mapCloudIds(assetsToUpsert);
 
       return true;
     } catch (e, s) {
@@ -336,28 +328,17 @@ class LocalSyncService {
     return true;
   }
 
-  // ignore: avoid-unused-parameters
-  Future<void> _mapIosCloudIds(List<LocalAsset> assets) async {
-    // if (!CurrentPlatform.isIOS || assets.isEmpty) {
-    return;
-    // }
+  Future<void> _mapCloudIds(List<LocalAsset> assets) async {
+    if (!CurrentPlatform.isIOS || assets.isEmpty) {
+      return;
+    }
 
-    // final assetIds = assets.map((a) => a.id).toList();
-    // final cloudMapping = <String, String>{};
-    // final cloudIds = await _nativeSyncApi.getCloudIdForAssetIds(assetIds);
-    // for (int i = 0; i < cloudIds.length; i++) {
-    //   final cloudIdResult = cloudIds[i];
-    //   if (cloudIdResult.cloudId != null) {
-    //     cloudMapping[cloudIdResult.assetId] = cloudIdResult.cloudId!;
-    //   } else {
-    //     final asset = assets.firstWhereOrNull((a) => a.id == cloudIdResult.assetId);
-    //     _log.fine(
-    //       "Cannot fetch cloudId for asset with id: ${cloudIdResult.assetId}, name: ${asset?.name}, createdAt: ${asset?.createdAt}. Error: ${cloudIdResult.error ?? "unknown"}",
-    //     );
-    //   }
-    // }
-
-    // await _localAlbumRepository.updateCloudMapping(cloudMapping);
+    await resolveCloudIds(
+      _nativeSyncApi,
+      _localAlbumRepository,
+      assets.map((a) => a.id).toList(),
+      cancellation: _cancellation,
+    );
   }
 
   bool _assetsEqual(LocalAsset a, LocalAsset b) {
diff --git a/mobile/lib/domain/utils/cloud_id_resolver.dart b/mobile/lib/domain/utils/cloud_id_resolver.dart
new file mode 100644
index 0000000000..21e50e8da4
--- /dev/null
+++ b/mobile/lib/domain/utils/cloud_id_resolver.dart
@@ -0,0 +1,55 @@
+import 'dart:async';
+
+import 'package:collection/collection.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/services.dart';
+import 'package:immich_mobile/infrastructure/repositories/local_album.repository.dart';
+import 'package:immich_mobile/platform/native_sync_api.g.dart';
+import 'package:logging/logging.dart';
+
+@visibleForTesting
+const kCloudIdChunkSize = 5000;
+
+Future<void> resolveCloudIds(
+  NativeSyncApi nativeSyncApi,
+  DriftLocalAlbumRepository albumRepository,
+  List<String> assetIds, {
+  Completer<void>? cancellation,
+}) async {
+  final logger = Logger('resolveCloudIds');
+
+  for (final batch in assetIds.slices(kCloudIdChunkSize)) {
+    if (cancellation?.isCompleted ?? false) {
+      logger.warning('Cloud ID resolution cancelled');
+      return;
+    }
+
+    final List<CloudIdResult> results;
+    try {
+      results = await nativeSyncApi.getCloudIdForAssetIds(batch);
+    } on PlatformException catch (error, stack) {
+      if (error.code == kUnSupportedOSError) {
+        logger.warning('Cloud IDs are unavailable on this device. Skipping resolution.', error, stack);
+        return;
+      }
+
+      logger.warning('Cannot fetch cloudIds for ${batch.length} assets. Skipping batch.', error, stack);
+      continue;
+    }
+
+    final cloudMapping = <String, String>{};
+    for (final CloudIdResult(:assetId, :cloudId, :error, :errorKind) in results) {
+      if (cloudId == null) {
+        logger.fine(
+          'Cannot fetch cloudId for asset with id: $assetId. '
+          'Reason: ${errorKind?.name ?? "unknown"}. Error: ${error ?? "unknown"}',
+        );
+        continue;
+      }
+
+      cloudMapping[assetId] = cloudId;
+    }
+
+    await albumRepository.updateCloudMapping(cloudMapping);
+  }
+}
diff --git a/mobile/lib/domain/utils/migrate_cloud_ids.dart b/mobile/lib/domain/utils/migrate_cloud_ids.dart
index efef6e8327..d161dded59 100644
--- a/mobile/lib/domain/utils/migrate_cloud_ids.dart
+++ b/mobile/lib/domain/utils/migrate_cloud_ids.dart
@@ -1,18 +1,21 @@
 import 'dart:async';
 
+import 'package:collection/collection.dart';
 import 'package:drift/drift.dart';
+import 'package:flutter/foundation.dart';
 import 'package:hooks_riverpod/hooks_riverpod.dart';
 import 'package:immich_mobile/constants/constants.dart';
 import 'package:immich_mobile/domain/models/asset/asset_metadata.model.dart';
 import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
+import 'package:immich_mobile/domain/utils/cloud_id_resolver.dart';
 import 'package:immich_mobile/extensions/platform_extensions.dart';
-import 'package:immich_mobile/infrastructure/entities/local_asset.entity.dart';
 import 'package:immich_mobile/infrastructure/repositories/db.repository.dart';
 import 'package:immich_mobile/infrastructure/repositories/local_album.repository.dart';
 import 'package:immich_mobile/platform/native_sync_api.g.dart';
 import 'package:immich_mobile/providers/api.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/cancel.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/db.provider.dart';
+import 'package:immich_mobile/providers/infrastructure/platform.provider.dart';
 import 'package:immich_mobile/providers/infrastructure/sync.provider.dart';
 import 'package:immich_mobile/providers/server_info.provider.dart';
 import 'package:immich_mobile/providers/user.provider.dart';
@@ -20,6 +23,10 @@ import 'package:logging/logging.dart';
 // ignore: import_rule_openapi
 import 'package:openapi/api.dart' hide AssetVisibility;
 
+const _kDbPageSize = 20000;
+
+const _kUploadBatchSize = 5000;
+
 Future<void> syncCloudIds(ProviderContainer ref) async {
   if (!CurrentPlatform.isIOS) {
     return;
@@ -27,8 +34,9 @@ Future<void> syncCloudIds(ProviderContainer ref) async {
   final logger = Logger('migrateCloudIds');
 
   final db = ref.read(driftProvider);
-  // Populate cloud IDs for local assets that don't have one yet
-  await _populateCloudIds(db);
+  final cancellation = ref.read(cancellationProvider);
+
+  await populateMissingCloudIds(db, ref.read(nativeSyncApiProvider), cancellation);
 
   final serverInfo = await ref.read(serverInfoProvider.notifier).getServerInfo();
   final canUpdateMetadata = serverInfo.serverVersion.isAtLeast(major: 2, minor: 4);
@@ -54,7 +62,6 @@ Future<void> syncCloudIds(ProviderContainer ref) async {
   }
 
   final assetApi = ref.read(apiServiceProvider).assetsApi;
-  final cancellation = ref.read(cancellationProvider);
 
   // Process cloud IDs in paginated batches
   await _processCloudIdMappingsInBatches(db, currentUser.id, assetApi, canBulkUpdateMetadata, logger, cancellation);
@@ -68,59 +75,137 @@ Future<void> _processCloudIdMappingsInBatches(
   Logger logger,
   Completer<void> cancellation,
 ) async {
-  const pageSize = 20000;
-  String? lastLocalId;
-  final seenRemoteAssetIds = <String>{};
+  String? lastRemoteId;
 
   while (true) {
     if (cancellation.isCompleted) {
       logger.warning('Cloud ID migration cancelled. Stopping batch processing.');
       break;
     }
-    final mappings = await _fetchCloudIdMappings(drift, userId, pageSize, lastLocalId);
+    final mappings = await fetchMapping(drift, userId, _kDbPageSize, lastRemoteId);
     if (mappings.isEmpty) {
       break;
     }
 
     final items = <AssetMetadataBulkUpsertItemDto>[];
     for (final mapping in mappings) {
-      if (seenRemoteAssetIds.add(mapping.remoteAssetId)) {
-        items.add(
-          AssetMetadataBulkUpsertItemDto(
-            assetId: mapping.remoteAssetId,
-            key: kMobileMetadataKey,
-            value: Map<String, Object>.from(
-              RemoteAssetMobileAppMetadata(
-                cloudId: mapping.localAsset.cloudId,
-                createdAt: mapping.localAsset.createdAt.toIso8601String(),
-                adjustmentTime: mapping.localAsset.adjustmentTime?.toIso8601String(),
-                latitude: mapping.localAsset.latitude?.toString(),
-                longitude: mapping.localAsset.longitude?.toString(),
-              ).toJson(),
-            ),
+      items.add(
+        .new(
+          assetId: mapping.remoteAssetId,
+          key: kMobileMetadataKey,
+          value: Map<String, Object>.from(
+            RemoteAssetMobileAppMetadata(
+              cloudId: mapping.cloudId,
+              createdAt: mapping.createdAt.toIso8601String(),
+              adjustmentTime: mapping.adjustmentTime?.toIso8601String(),
+              latitude: mapping.latitude?.toString(),
+              longitude: mapping.longitude?.toString(),
+            ).toJson(),
           ),
-        );
-      } else {
-        logger.fine('Duplicate remote asset ID found: ${mapping.remoteAssetId}. Skipping duplicate entry.');
-      }
+        ),
+      );
     }
 
     if (items.isNotEmpty) {
       if (canBulkUpdate) {
-        await _bulkUpdateCloudIds(assetsApi, items, cancellation.future);
+        for (final batch in items.slices(_kUploadBatchSize)) {
+          if (cancellation.isCompleted) {
+            break;
+          }
+
+          await _bulkUpdate(assetsApi, batch, cancellation.future);
+        }
       } else {
-        await _sequentialUpdateCloudIds(assetsApi, items, cancellation);
+        await _sequentialUpdate(assetsApi, items, cancellation);
       }
     }
 
-    lastLocalId = mappings.last.localAsset.id;
-    if (mappings.length < pageSize) {
+    lastRemoteId = mappings.last.remoteAssetId;
+    if (mappings.length < _kDbPageSize) {
       break;
     }
   }
 }
 
-Future<void> _sequentialUpdateCloudIds(
+@visibleForTesting
+Future<void> populateMissingCloudIds(Drift drift, NativeSyncApi nativeSyncApi, Completer<void> cancellation) async {
+  final query = drift.localAssetEntity.selectOnly()
+    ..addColumns([drift.localAssetEntity.id])
+    ..where(drift.localAssetEntity.iCloudId.isNull());
+  final ids = await query.map((row) => row.read(drift.localAssetEntity.id)!).get();
+
+  await resolveCloudIds(nativeSyncApi, DriftLocalAlbumRepository(drift), ids, cancellation: cancellation);
+}
+
+@visibleForTesting
+typedef CloudIdMapping = ({
+  String remoteAssetId,
+  String cloudId,
+  DateTime createdAt,
+  DateTime? adjustmentTime,
+  double? latitude,
+  double? longitude,
+});
+
+@visibleForTesting
+Future<List<CloudIdMapping>> fetchMapping(Drift db, String userId, int limit, String? lastRemoteId) async {
+  final query = db.remoteAssetEntity.selectOnly()
+    ..addColumns([
+      db.remoteAssetEntity.id,
+      db.localAssetEntity.iCloudId,
+      db.localAssetEntity.createdAt,
+      db.localAssetEntity.adjustmentTime,
+      db.localAssetEntity.latitude,
+      db.localAssetEntity.longitude,
+    ])
+    ..join([
+      innerJoin(
+        db.localAssetEntity,
+        db.localAssetEntity.id.isInQuery(
+          db.localAssetEntity.selectOnly()
+            ..addColumns([db.localAssetEntity.id.min()])
+            ..where(db.localAssetEntity.checksum.equalsExp(db.remoteAssetEntity.checksum)),
+        ),
+        useColumns: false,
+      ),
+      leftOuterJoin(
+        db.remoteAssetCloudIdEntity,
+        db.remoteAssetEntity.id.equalsExp(db.remoteAssetCloudIdEntity.assetId),
+        useColumns: false,
+      ),
+    ])
+    ..where(
+      db.remoteAssetEntity.ownerId.equals(userId) &
+          // Skip locked assets as we cannot update them without unlocking first
+          db.remoteAssetEntity.visibility.isNotValue(AssetVisibility.locked.index) &
+          db.localAssetEntity.iCloudId.isNotNull() &
+          // Only select assets that have a local cloud ID but either no remote cloud ID or a mismatched eTag
+          (db.remoteAssetCloudIdEntity.cloudId.isNull() |
+              db.remoteAssetCloudIdEntity.adjustmentTime.isNotExp(db.localAssetEntity.adjustmentTime) |
+              db.remoteAssetCloudIdEntity.latitude.isNotExp(db.localAssetEntity.latitude) |
+              db.remoteAssetCloudIdEntity.longitude.isNotExp(db.localAssetEntity.longitude) |
+              db.remoteAssetCloudIdEntity.createdAt.isNotExp(db.localAssetEntity.createdAt)),
+    )
+    ..orderBy([.asc(db.remoteAssetEntity.id)])
+    ..limit(limit);
+
+  if (lastRemoteId != null) {
+    query.where(db.remoteAssetEntity.id.isBiggerThanValue(lastRemoteId));
+  }
+
+  return query.map((row) {
+    return (
+      remoteAssetId: row.read(db.remoteAssetEntity.id)!,
+      cloudId: row.read(db.localAssetEntity.iCloudId)!,
+      createdAt: row.read(db.localAssetEntity.createdAt)!,
+      adjustmentTime: row.read(db.localAssetEntity.adjustmentTime),
+      latitude: row.read(db.localAssetEntity.latitude),
+      longitude: row.read(db.localAssetEntity.longitude),
+    );
+  }).get();
+}
+
+Future<void> _sequentialUpdate(
   AssetsApi assetsApi,
   List<AssetMetadataBulkUpsertItemDto> items,
   Completer<void> cancellation,
@@ -129,11 +214,12 @@ Future<void> _sequentialUpdateCloudIds(
     if (cancellation.isCompleted) {
       break;
     }
-    final upsertItem = AssetMetadataUpsertItemDto(key: item.key, value: item.value);
     try {
       await assetsApi.updateAssetMetadata(
         item.assetId,
-        AssetMetadataUpsertDto(items: [upsertItem]),
+        .new(
+          items: [.new(key: item.key, value: item.value)],
+        ),
         abortTrigger: cancellation.future,
       );
     } catch (error, stack) {
@@ -142,76 +228,14 @@ Future<void> _sequentialUpdateCloudIds(
   }
 }
 
-Future<void> _bulkUpdateCloudIds(
+Future<void> _bulkUpdate(
   AssetsApi assetsApi,
   List<AssetMetadataBulkUpsertItemDto> items,
   Future<void> abortTrigger,
 ) async {
   try {
-    await assetsApi.updateBulkAssetMetadata(AssetMetadataBulkUpsertDto(items: items), abortTrigger: abortTrigger);
+    await assetsApi.updateBulkAssetMetadata(.new(items: items), abortTrigger: abortTrigger);
   } catch (error, stack) {
     Logger('migrateCloudIds').warning('Failed to bulk update metadata', error, stack);
   }
 }
-
-Future<void> _populateCloudIds(Drift drift) async {
-  final query = drift.localAssetEntity.selectOnly()
-    ..addColumns([drift.localAssetEntity.id])
-    ..where(drift.localAssetEntity.iCloudId.isNull());
-  final ids = await query.map((row) => row.read(drift.localAssetEntity.id)!).get();
-  final cloudMapping = <String, String>{};
-  final cloudIds = await NativeSyncApi().getCloudIdForAssetIds(ids);
-  for (int i = 0; i < cloudIds.length; i++) {
-    final cloudIdResult = cloudIds[i];
-    if (cloudIdResult.cloudId != null) {
-      cloudMapping[cloudIdResult.assetId] = cloudIdResult.cloudId!;
-    } else {
-      Logger('migrateCloudIds').fine(
-        "Cannot fetch cloudId for asset with id: ${cloudIdResult.assetId}. Error: ${cloudIdResult.error ?? "unknown"}",
-      );
-    }
-  }
-  await DriftLocalAlbumRepository(drift).updateCloudMapping(cloudMapping);
-}
-
-typedef _CloudIdMapping = ({String remoteAssetId, LocalAsset localAsset});
-
-Future<List<_CloudIdMapping>> _fetchCloudIdMappings(Drift drift, String userId, int limit, String? lastLocalId) async {
-  final query =
-      drift.localAssetEntity.select().join([
-          innerJoin(
-            drift.remoteAssetEntity,
-            drift.localAssetEntity.checksum.equalsExp(drift.remoteAssetEntity.checksum),
-          ),
-          leftOuterJoin(
-            drift.remoteAssetCloudIdEntity,
-            drift.remoteAssetEntity.id.equalsExp(drift.remoteAssetCloudIdEntity.assetId),
-            useColumns: false,
-          ),
-        ])
-        ..where(
-          // Only select assets that have a local cloud ID but either no remote cloud ID or a mismatched eTag
-          drift.localAssetEntity.iCloudId.isNotNull() &
-              drift.remoteAssetEntity.ownerId.equals(userId) &
-              // Skip locked assets as we cannot update them without unlocking first
-              drift.remoteAssetEntity.visibility.isNotValue(AssetVisibility.locked.index) &
-              (drift.remoteAssetCloudIdEntity.cloudId.isNull() |
-                  drift.remoteAssetCloudIdEntity.adjustmentTime.isNotExp(drift.localAssetEntity.adjustmentTime) |
-                  drift.remoteAssetCloudIdEntity.latitude.isNotExp(drift.localAssetEntity.latitude) |
-                  drift.remoteAssetCloudIdEntity.longitude.isNotExp(drift.localAssetEntity.longitude) |
-                  drift.remoteAssetCloudIdEntity.createdAt.isNotExp(drift.localAssetEntity.createdAt)),
-        )
-        ..orderBy([OrderingTerm.asc(drift.localAssetEntity.id)])
-        ..limit(limit);
-
-  if (lastLocalId != null) {
-    query.where(drift.localAssetEntity.id.isBiggerThanValue(lastLocalId));
-  }
-
-  return query.map((row) {
-    return (
-      remoteAssetId: row.read(drift.remoteAssetEntity.id)!,
-      localAsset: row.readTable(drift.localAssetEntity).toDto(),
-    );
-  }).get();
-}
diff --git a/mobile/lib/infrastructure/repositories/local_asset.repository.dart b/mobile/lib/infrastructure/repositories/local_asset.repository.dart
index 8396d6d2a6..8e5c683a6b 100644
--- a/mobile/lib/infrastructure/repositories/local_asset.repository.dart
+++ b/mobile/lib/infrastructure/repositories/local_asset.repository.dart
@@ -217,11 +217,6 @@ class DriftLocalAssetRepository extends DriftDatabaseRepository {
     return RemovalCandidatesResult(assets: assets, totalBytes: totalBytes);
   }
 
-  Future<List<LocalAsset>> getEmptyCloudIdAssets() {
-    final query = _db.localAssetEntity.select()..where((row) => row.iCloudId.isNull());
-    return query.map((row) => row.toDto()).get();
-  }
-
   Future<void> reconcileHashesFromCloudId() async {
     await _db.customUpdate(
       '''
diff --git a/mobile/lib/pages/common/splash_screen.page.dart b/mobile/lib/pages/common/splash_screen.page.dart
index 65a78aed8a..8e8da3d9b1 100644
--- a/mobile/lib/pages/common/splash_screen.page.dart
+++ b/mobile/lib/pages/common/splash_screen.page.dart
@@ -337,8 +337,7 @@ class SplashScreenPageState extends ConsumerState<SplashScreenPage> {
                         unawaited(_resumeBackup(backupProvider));
                       }),
                       _resumeBackup(backupProvider),
-                      // TODO: Bring back when the soft freeze issue is addressed
-                      // backgroundManager.syncCloudIds(),
+                      backgroundManager.syncCloudIds(),
                     ]);
                   } else {
                     await backgroundManager.hashAssets();
diff --git a/mobile/lib/providers/app_life_cycle.provider.dart b/mobile/lib/providers/app_life_cycle.provider.dart
index f369a37142..de0daf8aa6 100644
--- a/mobile/lib/providers/app_life_cycle.provider.dart
+++ b/mobile/lib/providers/app_life_cycle.provider.dart
@@ -135,8 +135,7 @@ class AppLifeCycleNotifier extends StateNotifier<AppLifeCycleEnum> {
             unawaited(_resumeBackup());
           }),
           _resumeBackup(),
-          // TODO: Bring back when the soft freeze issue is addressed
-          // _safeRun(backgroundManager.syncCloudIds(), "syncCloudIds"),
+          _safeRun(backgroundManager.syncCloudIds, "syncCloudIds"),
         ]);
       } else {
         await _safeRun(backgroundManager.hashAssets, "hashAssets");
diff --git a/mobile/lib/providers/infrastructure/sync.provider.dart b/mobile/lib/providers/infrastructure/sync.provider.dart
index 700b51f12d..68ef9e39dc 100644
--- a/mobile/lib/providers/infrastructure/sync.provider.dart
+++ b/mobile/lib/providers/infrastructure/sync.provider.dart
@@ -37,7 +37,6 @@ final syncStreamRepositoryProvider = Provider((ref) => SyncStreamRepository(ref.
 final localSyncServiceProvider = Provider(
   (ref) => LocalSyncService(
     localAlbumRepository: ref.watch(localAlbumRepository),
-    localAssetRepository: ref.watch(localAssetRepository),
     trashedLocalAssetRepository: ref.watch(trashedLocalAssetRepository),
     assetMediaRepository: ref.watch(assetMediaRepositoryProvider),
     permissionRepository: ref.watch(permissionRepositoryProvider),
diff --git a/mobile/pigeon/native_sync_api.dart b/mobile/pigeon/native_sync_api.dart
index 433b154cd1..f5a6d55e02 100644
--- a/mobile/pigeon/native_sync_api.dart
+++ b/mobile/pigeon/native_sync_api.dart
@@ -11,6 +11,8 @@ import 'package:pigeon/pigeon.dart';
     dartPackageName: 'immich_mobile',
   ),
 )
+const String kUnSupportedOSError = 'UNSUPPORTED_OS';
+
 enum PlatformAssetPlaybackStyle { unknown, image, video, imageAnimated, livePhoto, videoLooping }
 
 class PlatformAsset {
@@ -95,12 +97,23 @@ class HashResult {
   const HashResult({required this.assetId, this.error, this.hash});
 }
 
+enum CloudIdErrorKind {
+  // PHPhotosErrorIdentifierNotFound
+  notFound,
+  // PHPhotosErrorMultipleIdentifiersFound
+  ambiguous,
+  // PhotoKit returned a partially synced identifier ("GUID:ID:" with no trailing hash)
+  incomplete,
+  unknown,
+}
+
 class CloudIdResult {
   final String assetId;
   final String? error;
   final String? cloudId;
+  final CloudIdErrorKind? errorKind;
 
-  const CloudIdResult({required this.assetId, this.error, this.cloudId});
+  const CloudIdResult({required this.assetId, this.error, this.cloudId, this.errorKind});
 }
 
 @HostApi()
diff --git a/mobile/pubspec.lock b/mobile/pubspec.lock
index ac19481079..d7d03c1177 100644
--- a/mobile/pubspec.lock
+++ b/mobile/pubspec.lock
@@ -1362,10 +1362,10 @@ packages:
     dependency: "direct dev"
     description:
       name: pigeon
-      sha256: "04cfefc8add8b47ddf9ccac8b92bb4edeb67c87f185c623ba0db118ac99334ad"
+      sha256: f90254ef7b22db026fd8d5fd44718fd60697d50968a144a8bc251e5e95d79e10
       url: "https://pub.dev"
     source: hosted
-    version: "26.3.4"
+    version: "27.3.0"
   pinput:
     dependency: "direct main"
     description:
diff --git a/mobile/pubspec.yaml b/mobile/pubspec.yaml
index 32e67de4f6..10d8e9392a 100644
--- a/mobile/pubspec.yaml
+++ b/mobile/pubspec.yaml
@@ -110,7 +110,7 @@ dev_dependencies:
     sdk: flutter
   mocktail: ^1.0.5
   # Type safe platform code
-  pigeon: ^26.3.4
+  pigeon: ^27.3.0
 
 # cast 2.1.0 declares a loose bonsoir range but its code targets the 5.x API.
 # Pin bonsoir to 5.x until cast releases a version compatible with bonsoir 6.x.
diff --git a/mobile/test/domain/services/local_sync_service_test.dart b/mobile/test/domain/services/local_sync_service_test.dart
index 14277709da..00bea08b22 100644
--- a/mobile/test/domain/services/local_sync_service_test.dart
+++ b/mobile/test/domain/services/local_sync_service_test.dart
@@ -9,7 +9,6 @@ import 'package:immich_mobile/domain/services/store.service.dart';
 import 'package:immich_mobile/entities/store.entity.dart';
 import 'package:immich_mobile/infrastructure/repositories/db.repository.dart';
 import 'package:immich_mobile/infrastructure/repositories/local_album.repository.dart';
-import 'package:immich_mobile/infrastructure/repositories/local_asset.repository.dart';
 import 'package:immich_mobile/infrastructure/repositories/store.repository.dart';
 import 'package:immich_mobile/infrastructure/repositories/trashed_local_asset.repository.dart';
 import 'package:immich_mobile/platform/native_sync_api.g.dart';
@@ -24,7 +23,6 @@ import '../../service.mocks.dart';
 void main() {
   late LocalSyncService sut;
   late DriftLocalAlbumRepository mockLocalAlbumRepository;
-  late DriftLocalAssetRepository mockLocalAssetRepository;
   late DriftTrashedLocalAssetRepository mockTrashedLocalAssetRepository;
   late AssetMediaRepository mockAssetMediaRepository;
   late MockPermissionRepository mockPermissionRepository;
@@ -47,7 +45,6 @@ void main() {
 
   setUp(() async {
     mockLocalAlbumRepository = MockLocalAlbumRepository();
-    mockLocalAssetRepository = MockLocalAssetRepository();
     mockTrashedLocalAssetRepository = MockTrashedLocalAssetRepository();
     mockAssetMediaRepository = MockAssetMediaRepository();
     mockPermissionRepository = MockPermissionRepository();
@@ -70,7 +67,6 @@ void main() {
 
     sut = LocalSyncService(
       localAlbumRepository: mockLocalAlbumRepository,
-      localAssetRepository: mockLocalAssetRepository,
       trashedLocalAssetRepository: mockTrashedLocalAssetRepository,
       assetMediaRepository: mockAssetMediaRepository,
       permissionRepository: mockPermissionRepository,
diff --git a/mobile/test/medium/repositories/local_asset_repository_test.dart b/mobile/test/medium/repositories/local_asset_repository_test.dart
index 2376445d1a..3d21e961d0 100644
--- a/mobile/test/medium/repositories/local_asset_repository_test.dart
+++ b/mobile/test/medium/repositories/local_asset_repository_test.dart
@@ -559,8 +559,8 @@ void main() {
       final remoteAsset = await ctx.newRemoteAsset(ownerId: userId);
       final cloudIdAsset = await ctx.newRemoteAssetCloudId(id: remoteAsset.id);
       final localAsset = await ctx.newLocalAsset(
-        checksumOption: const Option.none(),
-        iCloudId: null,
+        checksumOption: const .none(),
+        iCloudIdOption: const .none(),
         createdAt: cloudIdAsset.createdAt,
         adjustmentTime: cloudIdAsset.adjustmentTime,
         latitude: cloudIdAsset.latitude,
diff --git a/mobile/test/medium/repository_context.dart b/mobile/test/medium/repository_context.dart
index 09b8e2c7eb..0f02350a21 100644
--- a/mobile/test/medium/repository_context.dart
+++ b/mobile/test/medium/repository_context.dart
@@ -271,6 +271,7 @@ class MediumRepositoryContext {
     AssetType? type,
     bool? isFavorite,
     String? iCloudId,
+    Option<String>? iCloudIdOption,
     DateTime? adjustmentTime,
     Option<DateTime>? adjustmentTimeOption,
     double? latitude,
@@ -297,7 +298,7 @@ class MediumRepositoryContext {
             createdAt: .new(TestUtils.date(createdAt)),
             type: .new(type ?? .image),
             isFavorite: .new(isFavorite ?? false),
-            iCloudId: .new(TestUtils.uuid(iCloudId)),
+            iCloudId: _resolveUndefined(iCloudId, iCloudIdOption, TestUtils.uuid()),
             adjustmentTime: _resolveUndefined(adjustmentTime, adjustmentTimeOption, DateTime.now()),
             latitude: .new(latitude ?? TestUtils.randDouble(-90, 90)),
             longitude: .new(longitude ?? TestUtils.randDouble(-180, 180)),
diff --git a/mobile/test/medium/utils/migrate_cloud_ids_test.dart b/mobile/test/medium/utils/migrate_cloud_ids_test.dart
new file mode 100644
index 0000000000..38585dd755
--- /dev/null
+++ b/mobile/test/medium/utils/migrate_cloud_ids_test.dart
@@ -0,0 +1,112 @@
+import 'dart:async';
+
+import 'package:drift/drift.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:immich_mobile/domain/utils/cloud_id_resolver.dart';
+import 'package:immich_mobile/domain/utils/migrate_cloud_ids.dart';
+import 'package:immich_mobile/infrastructure/repositories/local_album.repository.dart';
+import 'package:immich_mobile/platform/native_sync_api.g.dart';
+import 'package:mocktail/mocktail.dart';
+
+import '../../service.mocks.dart';
+import '../repository_context.dart';
+
+void main() {
+  late MediumRepositoryContext ctx;
+  late MockNativeSyncApi mockNativeSyncApi;
+  late DriftLocalAlbumRepository albumRepository;
+
+  setUp(() {
+    ctx = MediumRepositoryContext();
+    mockNativeSyncApi = MockNativeSyncApi();
+    albumRepository = DriftLocalAlbumRepository(ctx.db);
+  });
+
+  tearDown(() async {
+    await ctx.dispose();
+  });
+
+  Future<List<String?>> readCloudIds() async {
+    final rows = await ctx.db.localAssetEntity.select().get();
+    return rows.map((row) => row.iCloudId).toList();
+  }
+
+  void resolvingAllInputs() {
+    when(() => mockNativeSyncApi.getCloudIdForAssetIds(any())).thenAnswer(
+      (invocation) async => (invocation.positionalArguments.first as List<String>)
+          .map((id) => CloudIdResult(assetId: id, cloudId: 'cloud-$id'))
+          .toList(),
+    );
+  }
+
+  group('populateCloudIds', () {
+    test('writes the cloud ID resolved for each asset', () async {
+      await ctx.newLocalAsset(id: 'asset-0', iCloudIdOption: const .none());
+      resolvingAllInputs();
+
+      await populateMissingCloudIds(ctx.db, mockNativeSyncApi, .new());
+      expect(await readCloudIds(), ['cloud-asset-0']);
+    });
+
+    test('skips assets that already have a cloud ID', () async {
+      await ctx.newLocalAsset(iCloudId: 'existing');
+
+      await populateMissingCloudIds(ctx.db, mockNativeSyncApi, .new());
+
+      verifyNever(() => mockNativeSyncApi.getCloudIdForAssetIds(any()));
+      expect(await readCloudIds(), ['existing']);
+    });
+
+    test('does not call the native API when already cancelled', () async {
+      await ctx.newLocalAsset(iCloudIdOption: const .none());
+
+      await populateMissingCloudIds(ctx.db, mockNativeSyncApi, .new()..complete());
+
+      verifyNever(() => mockNativeSyncApi.getCloudIdForAssetIds(any()));
+      expect(await readCloudIds(), [null]);
+    });
+  });
+
+  group('resolveCloudIds', () {
+    test('resolves and stores more assets than fit in a single chunk', () async {
+      final ids = List.generate(kCloudIdChunkSize + 1, (i) => 'asset-$i');
+      for (final id in ids) {
+        await ctx.newLocalAsset(id: id, iCloudIdOption: const .none());
+      }
+      resolvingAllInputs();
+
+      await resolveCloudIds(mockNativeSyncApi, albumRepository, ids);
+
+      verify(() => mockNativeSyncApi.getCloudIdForAssetIds(any())).called(2);
+      final stored = await ctx.db.localAssetEntity.select().get();
+      expect(stored.every((row) => row.iCloudId == 'cloud-${row.id}'), isTrue);
+    });
+
+    test('stops after the first chunk when cloud IDs are unsupported', () async {
+      final ids = List.generate(kCloudIdChunkSize + 1, (i) => 'asset-$i');
+      when(
+        () => mockNativeSyncApi.getCloudIdForAssetIds(any()),
+      ).thenThrow(PlatformException(code: kUnSupportedOSError));
+
+      await resolveCloudIds(mockNativeSyncApi, albumRepository, ids);
+
+      verify(() => mockNativeSyncApi.getCloudIdForAssetIds(any())).called(1);
+    });
+
+    test('stops between chunks once cancelled', () async {
+      final ids = List.generate(kCloudIdChunkSize + 1, (i) => 'asset-$i');
+      final cancellation = Completer<void>();
+      when(() => mockNativeSyncApi.getCloudIdForAssetIds(any())).thenAnswer((invocation) async {
+        cancellation.complete();
+        return (invocation.positionalArguments.first as List<String>)
+            .map((id) => CloudIdResult(assetId: id, cloudId: 'cloud-$id'))
+            .toList();
+      });
+
+      await resolveCloudIds(mockNativeSyncApi, albumRepository, ids, cancellation: cancellation);
+
+      verify(() => mockNativeSyncApi.getCloudIdForAssetIds(any())).called(1);
+    });
+  });
+}