diff --git a/mobile/lib/db/collections_db.dart b/mobile/lib/db/collections_db.dart
index 178e81302e..e9597c62ca 100644
--- a/mobile/lib/db/collections_db.dart
+++ b/mobile/lib/db/collections_db.dart
@@ -251,7 +251,7 @@ class CollectionsDB {
   Map<String, dynamic> _getRowForCollection(Collection collection) {
     final row = <String, dynamic>{};
     row[columnID] = collection.id;
-    row[columnOwner] = collection.owner!.toJson();
+    row[columnOwner] = collection.owner.toJson();
     row[columnEncryptedKey] = collection.encryptedKey;
     row[columnKeyDecryptionNonce] = collection.keyDecryptionNonce;
     row[columnName] = collection.name;
@@ -262,9 +262,9 @@ class CollectionsDB {
     row[columnPathDecryptionNonce] = collection.attributes.pathDecryptionNonce;
     row[columnVersion] = collection.attributes.version;
     row[columnSharees] =
-        json.encode(collection.sharees?.map((x) => x?.toMap()).toList());
+        json.encode(collection.sharees.map((x) => x.toMap()).toList());
     row[columnPublicURLs] =
-        json.encode(collection.publicURLs?.map((x) => x?.toMap()).toList());
+        json.encode(collection.publicURLs.map((x) => x.toMap()).toList());
     row[columnUpdationTime] = collection.updationTime;
     if (collection.isDeleted) {
       row[columnIsDeleted] = _sqlBoolTrue;
diff --git a/mobile/lib/emergency/select_contact_page.dart b/mobile/lib/emergency/select_contact_page.dart
index c12be89bbd..a61828f3b1 100644
--- a/mobile/lib/emergency/select_contact_page.dart
+++ b/mobile/lib/emergency/select_contact_page.dart
@@ -322,22 +322,20 @@ class _AddContactPage extends State<AddContactPage> {
     final int ownerID = Configuration.instance.getUserID()!;
     existingEmails.add(Configuration.instance.getEmail()!);
     for (final c in CollectionsService.instance.getActiveCollections()) {
-      if (c.owner?.id == ownerID) {
-        for (final User? u in c.sharees ?? []) {
-          if (u != null &&
-              u.id != null &&
+      if (c.owner.id == ownerID) {
+        for (final User u in c.sharees) {
+          if (u.id != null &&
               u.email.isNotEmpty &&
               !existingEmails.contains(u.email)) {
             existingEmails.add(u.email);
             suggestedUsers.add(u);
           }
         }
-      } else if (c.owner != null &&
-          c.owner!.id != null &&
-          c.owner!.email.isNotEmpty &&
-          !existingEmails.contains(c.owner!.email)) {
-        existingEmails.add(c.owner!.email);
-        suggestedUsers.add(c.owner!);
+      } else if (c.owner.id != null &&
+          c.owner.email.isNotEmpty &&
+          !existingEmails.contains(c.owner.email)) {
+        existingEmails.add(c.owner.email);
+        suggestedUsers.add(c.owner);
       }
     }
     final cachedUserDetails = UserService.instance.getCachedUserDetails();
diff --git a/mobile/lib/models/collection/collection.dart b/mobile/lib/models/collection/collection.dart
index df15f47840..2330da3aa9 100644
--- a/mobile/lib/models/collection/collection.dart
+++ b/mobile/lib/models/collection/collection.dart
@@ -8,7 +8,7 @@ import "package:photos/models/metadata/common_keys.dart";
 
 class Collection {
   final int id;
-  final User? owner;
+  final User owner;
   final String encryptedKey;
   final String? keyDecryptionNonce;
   @Deprecated("Use collectionName instead")
@@ -20,8 +20,8 @@ class Collection {
   final String? nameDecryptionNonce;
   final CollectionType type;
   final CollectionAttributes attributes;
-  final List<User?>? sharees;
-  final List<PublicURL?>? publicURLs;
+  final List<User> sharees;
+  final List<PublicURL> publicURLs;
   final int updationTime;
   final bool isDeleted;
 
@@ -95,12 +95,12 @@ class Collection {
 
   // hasLink returns true if there's any link attached to the collection
   // including expired links
-  bool get hasLink => publicURLs != null && publicURLs!.isNotEmpty;
+  bool get hasLink => publicURLs.isNotEmpty;
 
   bool get hasCover => (pubMagicMetadata.coverID ?? 0) > 0;
 
   // hasSharees returns true if the collection is shared with other ente users
-  bool get hasSharees => sharees != null && sharees!.isNotEmpty;
+  bool get hasSharees => sharees.isNotEmpty;
 
   bool get isPinned => (magicMetadata.order ?? 0) != 0;
 
@@ -121,52 +121,43 @@ class Collection {
   }
 
   List<User> getSharees() {
-    final List<User> result = [];
-    if (sharees == null) {
-      return result;
-    }
-    for (final User? u in sharees!) {
-      if (u != null) {
-        result.add(u);
-      }
-    }
-    return result;
+    return sharees;
   }
 
   bool isOwner(int userID) {
-    return (owner?.id ?? 0) == userID;
+    return (owner.id ?? -100) == userID;
   }
 
   bool isDownloadEnabledForPublicLink() {
-    if (publicURLs == null || publicURLs!.isEmpty) {
+    if (publicURLs.isEmpty) {
       return false;
     }
-    return publicURLs?.first?.enableDownload ?? true;
+    return publicURLs.first.enableDownload;
   }
 
   bool isCollectEnabledForPublicLink() {
-    if (publicURLs == null || publicURLs!.isEmpty) {
+    if (publicURLs.isEmpty) {
       return false;
     }
-    return publicURLs?.first?.enableCollect ?? false;
+    return publicURLs.first.enableCollect;
   }
 
   bool get isJoinEnabled {
-    if (publicURLs == null || publicURLs!.isEmpty) {
+    if (publicURLs.isEmpty) {
       return false;
     }
-    return publicURLs?.first?.enableJoin ?? false;
+    return publicURLs.first.enableJoin;
   }
 
   CollectionParticipantRole getRole(int userID) {
     if (isOwner(userID)) {
       return CollectionParticipantRole.owner;
     }
-    if (sharees == null) {
+    if (sharees.isEmpty) {
       return CollectionParticipantRole.unknown;
     }
-    for (final User? u in sharees!) {
-      if (u != null && u.id == userID) {
+    for (final User u in sharees) {
+      if (u.id == userID) {
         if (u.isViewer) {
           return CollectionParticipantRole.viewer;
         } else if (u.isCollaborator) {
@@ -185,8 +176,8 @@ class Collection {
   }
 
   void updateSharees(List<User> newSharees) {
-    sharees?.clear();
-    sharees?.addAll(newSharees);
+    sharees.clear();
+    sharees.addAll(newSharees);
   }
 
   static CollectionType typeFromString(String type) {
diff --git a/mobile/lib/services/collections_service.dart b/mobile/lib/services/collections_service.dart
index 3bac9fe978..941f874d38 100644
--- a/mobile/lib/services/collections_service.dart
+++ b/mobile/lib/services/collections_service.dart
@@ -139,7 +139,7 @@ class CollectionsService {
         }
       }
       // remove reference for incoming collections when unshared/deleted
-      if (collection.isDeleted && ownerID != collection.owner?.id) {
+      if (collection.isDeleted && ownerID != collection.owner.id) {
         await _db.deleteCollection(collection.id);
       } else {
         // keep entry for deletedCollection as collectionKey may be used during
@@ -394,7 +394,7 @@ class CollectionsService {
     final List<Collection> collections =
         getCollectionsForUI(includedShared: true);
     for (final c in collections) {
-      if (c.owner!.id == Configuration.instance.getUserID()) {
+      if (c.owner.id == Configuration.instance.getUserID()) {
         if (c.hasSharees || c.hasLink && !c.isQuickLinkCollection()) {
           outgoing.add(c);
         } else if (c.isQuickLinkCollection()) {
@@ -472,8 +472,8 @@ class CollectionsService {
     if (collectionID != null) {
       final Collection? collection = getCollectionByID(collectionID);
       if (collection != null) {
-        if (collection.owner?.id == userID) {
-          _cachedUserIdToUser[userID] = collection.owner!;
+        if (collection.owner.id == userID) {
+          _cachedUserIdToUser[userID] = collection.owner;
         } else {
           final matchingUser = collection.getSharees().firstWhereOrNull(
                 (u) => u.id == userID,
@@ -698,7 +698,7 @@ class CollectionsService {
     );
     final encryptedKey = CryptoUtil.base642bin(collection.encryptedKey);
     Uint8List? collectionKey;
-    if (collection.owner?.id == _config.getUserID()) {
+    if (collection.owner.id == _config.getUserID()) {
       // If the collection is owned by the user, decrypt with the master key
       if (_config.getKey() == null) {
         // Possible during AppStore account migration, where SecureStorage
@@ -767,7 +767,7 @@ class CollectionsService {
   ) async {
     final int ownerID = Configuration.instance.getUserID()!;
     try {
-      if (collection.owner?.id != ownerID) {
+      if (collection.owner.id != ownerID) {
         throw AssertionError("cannot modify albums not owned by you");
       }
       // read the existing magic metadata and apply new updates to existing data
@@ -826,7 +826,7 @@ class CollectionsService {
   ) async {
     final int ownerID = Configuration.instance.getUserID()!;
     try {
-      if (collection.owner?.id != ownerID) {
+      if (collection.owner.id != ownerID) {
         throw AssertionError("cannot modify albums not owned by you");
       }
       // read the existing magic metadata and apply new updates to existing data
@@ -885,7 +885,7 @@ class CollectionsService {
   ) async {
     final int ownerID = Configuration.instance.getUserID()!;
     try {
-      if (collection.owner?.id == ownerID) {
+      if (collection.owner.id == ownerID) {
         throw AssertionError("cannot modify sharee settings for albums owned "
             "by you");
       }
@@ -952,7 +952,7 @@ class CollectionsService {
           "enableJoin": true,
         },
       );
-      collection.publicURLs?.add(PublicURL.fromMap(response.data["result"]));
+      collection.publicURLs.add(PublicURL.fromMap(response.data["result"]));
       await _db.insert(List.from([collection]));
       _collectionIDToCollections[collection.id] = collection;
       Bus.instance.fire(
@@ -980,8 +980,8 @@ class CollectionsService {
         data: json.encode(prop),
       );
       // remove existing url information
-      collection.publicURLs?.clear();
-      collection.publicURLs?.add(PublicURL.fromMap(response.data["result"]));
+      collection.publicURLs.clear();
+      collection.publicURLs.add(PublicURL.fromMap(response.data["result"]));
       await _db.insert(List.from([collection]));
       _collectionIDToCollections[collection.id] = collection;
       Bus.instance.fire(
@@ -1003,7 +1003,7 @@ class CollectionsService {
       await _enteDio.delete(
         "/collections/share-url/" + collection.id.toString(),
       );
-      collection.publicURLs?.clear();
+      collection.publicURLs.clear();
       await _db.insert(List.from([collection]));
       _collectionIDToCollections[collection.id] = collection;
       Bus.instance.fire(
diff --git a/mobile/lib/services/favorites_service.dart b/mobile/lib/services/favorites_service.dart
index 42a1252cf6..8623066247 100644
--- a/mobile/lib/services/favorites_service.dart
+++ b/mobile/lib/services/favorites_service.dart
@@ -230,7 +230,7 @@ class FavoritesService {
     if (_cachedFavoritesCollectionID == null) {
       final collections = _collectionsService.getActiveCollections();
       for (final collection in collections) {
-        if (collection.owner!.id == _config.getUserID() &&
+        if (collection.owner.id == _config.getUserID() &&
             collection.type == CollectionType.favorites) {
           _cachedFavoritesCollectionID = collection.id;
           return collection;
diff --git a/mobile/lib/services/hidden_service.dart b/mobile/lib/services/hidden_service.dart
index 53aeb24621..8705ab7afa 100644
--- a/mobile/lib/services/hidden_service.dart
+++ b/mobile/lib/services/hidden_service.dart
@@ -32,7 +32,7 @@ extension HiddenService on CollectionsService {
     final int userID = config.getUserID()!;
     final allDefaultHidden = collectionIDToCollections.values
         .where(
-          (element) => element.isDefaultHidden() && element.owner!.id == userID,
+          (element) => element.isDefaultHidden() && element.owner.id == userID,
         )
         .toList();
 
@@ -101,7 +101,7 @@ extension HiddenService on CollectionsService {
         collectionIDToCollections.values.firstWhereOrNull(
       (element) =>
           element.type == CollectionType.uncategorized &&
-          element.owner!.id == userID,
+          element.owner.id == userID,
     );
     if (matchedCollection != null) {
       cachedUncategorizedCollection = matchedCollection;
@@ -166,7 +166,9 @@ extension HiddenService on CollectionsService {
       await dialog.hide();
     } on AssertionError catch (e) {
       await dialog.hide();
-      unawaited(showErrorDialog(context, S.of(context).oops, e.message as String));
+      unawaited(
+        showErrorDialog(context, S.of(context).oops, e.message as String),
+      );
       return false;
     } catch (e, s) {
       _logger.severe("Could not hide", e, s);
diff --git a/mobile/lib/services/user_service.dart b/mobile/lib/services/user_service.dart
index 1098005f45..e33d088b26 100644
--- a/mobile/lib/services/user_service.dart
+++ b/mobile/lib/services/user_service.dart
@@ -1311,34 +1311,30 @@ class UserService {
 
     for (final c in CollectionsService.instance.getActiveCollections()) {
       // Add collaborators and viewers of collections owned by user
-      if (c.owner?.id == ownerID) {
-        for (final User? u in c.sharees ?? []) {
-          if (u != null && u.id != null && u.email.isNotEmpty) {
+      if (c.owner.id == ownerID) {
+        for (final User u in c.sharees) {
+          if (u.id != null && u.email.isNotEmpty) {
             if (!existingEmails.contains(u.email)) {
               relevantUsers.add(u);
               existingEmails.add(u.email);
             }
           }
         }
-      } else if (c.owner?.id != null && c.owner!.email.isNotEmpty) {
+      } else if (c.owner.id != null && c.owner.email.isNotEmpty) {
         // Add owners of collections shared with user
-        if (!existingEmails.contains(c.owner!.email)) {
-          relevantUsers.add(c.owner!);
-          existingEmails.add(c.owner!.email);
+        if (!existingEmails.contains(c.owner.email)) {
+          relevantUsers.add(c.owner);
+          existingEmails.add(c.owner.email);
         }
         // Add collaborators of collections shared with user where user is a
         // viewer or a collaborator
-        for (final User? u in c.sharees ?? []) {
-          if (u != null &&
-              u.id != null &&
+        for (final User u in c.sharees) {
+          if (u.id != null &&
               u.email.isNotEmpty &&
               u.email == ownerEmail &&
               (u.isCollaborator || u.isViewer)) {
-            for (final User? u in c.sharees ?? []) {
-              if (u != null &&
-                  u.id != null &&
-                  u.email.isNotEmpty &&
-                  u.isCollaborator) {
+            for (final User u in c.sharees) {
+              if (u.id != null && u.email.isNotEmpty && u.isCollaborator) {
                 if (!existingEmails.contains(u.email)) {
                   relevantUsers.add(u);
                   existingEmails.add(u.email);
@@ -1392,32 +1388,28 @@ class UserService {
 
     for (final c in CollectionsService.instance.getActiveCollections()) {
       // Add collaborators and viewers of collections owned by user
-      if (c.owner?.id == ownerID) {
-        for (final User? u in c.sharees ?? []) {
-          if (u != null && u.id != null && u.email.isNotEmpty) {
+      if (c.owner.id == ownerID) {
+        for (final User u in c.sharees) {
+          if (u.id != null && u.email.isNotEmpty) {
             if (!emailIDs.contains(u.email)) {
               emailIDs.add(u.email);
             }
           }
         }
-      } else if (c.owner?.id != null && c.owner!.email.isNotEmpty) {
+      } else if (c.owner.id != null && c.owner.email.isNotEmpty) {
         // Add owners of collections shared with user
-        if (!emailIDs.contains(c.owner!.email)) {
-          emailIDs.add(c.owner!.email);
+        if (!emailIDs.contains(c.owner.email)) {
+          emailIDs.add(c.owner.email);
         }
         // Add collaborators of collections shared with user where user is a
         // viewer or a collaborator
-        for (final User? u in c.sharees ?? []) {
-          if (u != null &&
-              u.id != null &&
+        for (final User u in c.sharees) {
+          if (u.id != null &&
               u.email.isNotEmpty &&
               u.email == ownerEmail &&
               (u.isCollaborator || u.isViewer)) {
-            for (final User? u in c.sharees ?? []) {
-              if (u != null &&
-                  u.id != null &&
-                  u.email.isNotEmpty &&
-                  u.isCollaborator) {
+            for (final User u in c.sharees) {
+              if (u.id != null && u.email.isNotEmpty && u.isCollaborator) {
                 if (!emailIDs.contains(u.email)) {
                   emailIDs.add(u.email);
                 }
diff --git a/mobile/lib/ui/actions/collection/collection_file_actions.dart b/mobile/lib/ui/actions/collection/collection_file_actions.dart
index 81b79825ac..81bdcefb3b 100644
--- a/mobile/lib/ui/actions/collection/collection_file_actions.dart
+++ b/mobile/lib/ui/actions/collection/collection_file_actions.dart
@@ -147,7 +147,7 @@ extension CollectionFileActions on CollectionActions {
         // Newly created collection might not be cached
         final Collection? c =
             CollectionsService.instance.getCollectionByID(collectionID);
-        if (c != null && c.owner!.id != currentUserID) {
+        if (c != null && c.owner.id != currentUserID) {
           if (!showProgressDialog) {
             dialog = createProgressDialog(
               context,
diff --git a/mobile/lib/ui/actions/collection/collection_sharing_actions.dart b/mobile/lib/ui/actions/collection/collection_sharing_actions.dart
index c2c354cf77..1cf642dff0 100644
--- a/mobile/lib/ui/actions/collection/collection_sharing_actions.dart
+++ b/mobile/lib/ui/actions/collection/collection_sharing_actions.dart
@@ -340,7 +340,7 @@ class CollectionActions {
   ) async {
     final textTheme = getEnteTextTheme(bContext);
     final currentUserID = Configuration.instance.getUserID()!;
-    if (collection.owner!.id != currentUserID) {
+    if (collection.owner.id != currentUserID) {
       throw AssertionError("Can not delete album owned by others");
     }
     if (collection.hasSharees) {
@@ -495,7 +495,7 @@ class CollectionActions {
     bool isHidden = false,
   }) async {
     final int currentUserID = Configuration.instance.getUserID()!;
-    final isCollectionOwner = collection.owner!.id == currentUserID;
+    final isCollectionOwner = collection.owner.id == currentUserID;
     final FilesSplit split = FilesSplit.split(
       files,
       Configuration.instance.getUserID()!,
@@ -631,7 +631,7 @@ class CollectionActions {
     if (targetCollection == null ||
         (CollectionType.uncategorized == targetCollection.type ||
             targetCollection.type == CollectionType.favorites) ||
-        targetCollection.owner!.id != userID) {
+        targetCollection.owner.id != userID) {
       return false;
     }
     return true;
diff --git a/mobile/lib/ui/collections/album/row_item.dart b/mobile/lib/ui/collections/album/row_item.dart
index 50b96420ef..5f684d3780 100644
--- a/mobile/lib/ui/collections/album/row_item.dart
+++ b/mobile/lib/ui/collections/album/row_item.dart
@@ -41,7 +41,7 @@ class AlbumRowItemWidget extends StatelessWidget {
     final Widget? linkIcon = c.hasLink && isOwner
         ? Icon(
             Icons.link,
-            color: c.publicURLs!.first!.isExpired ? warning500 : strokeBaseDark,
+            color: c.publicURLs.first.isExpired ? warning500 : strokeBaseDark,
           )
         : null;
     return GestureDetector(
@@ -115,7 +115,7 @@ class AlbumRowItemWidget extends StatelessWidget {
                                 bottom: 8.0,
                               ),
                               child: UserAvatarWidget(
-                                c.owner!,
+                                c.owner,
                                 thumbnailView: true,
                               ),
                             ),
diff --git a/mobile/lib/ui/collections/album/vertical_list.dart b/mobile/lib/ui/collections/album/vertical_list.dart
index 17a0308ce0..d6d4a4c07c 100644
--- a/mobile/lib/ui/collections/album/vertical_list.dart
+++ b/mobile/lib/ui/collections/album/vertical_list.dart
@@ -287,8 +287,8 @@ class AlbumVerticalListWidget extends StatelessWidget {
         CollectionActions(CollectionsService.instance);
 
     if (collection.hasLink) {
-      if (collection.publicURLs!.first!.enableCollect) {
-        if (Configuration.instance.getUserID() == collection.owner!.id) {
+      if (collection.publicURLs.first.enableCollect) {
+        if (Configuration.instance.getUserID() == collection.owner.id) {
           unawaited(
             routeToPage(
               context,
@@ -334,7 +334,7 @@ class AlbumVerticalListWidget extends StatelessWidget {
         context,
         S.of(context).collaborativeLinkCreatedFor(collection.displayName),
       );
-      if (Configuration.instance.getUserID() == collection.owner!.id) {
+      if (Configuration.instance.getUserID() == collection.owner.id) {
         unawaited(
           routeToPage(
             context,
@@ -353,7 +353,7 @@ class AlbumVerticalListWidget extends StatelessWidget {
     BuildContext context,
     Collection collection,
   ) {
-    if (Configuration.instance.getUserID() == collection.owner!.id) {
+    if (Configuration.instance.getUserID() == collection.owner.id) {
       unawaited(
         routeToPage(
           context,
diff --git a/mobile/lib/ui/sharing/add_participant_page.dart b/mobile/lib/ui/sharing/add_participant_page.dart
index cfa48d037a..6c7b064014 100644
--- a/mobile/lib/ui/sharing/add_participant_page.dart
+++ b/mobile/lib/ui/sharing/add_participant_page.dart
@@ -363,8 +363,8 @@ class _AddParticipantPage extends State<AddParticipantPage> {
 
   List<User> _getSuggestedUser() {
     final Set<String> existingEmails = {};
-    for (final User? u in widget.collection.sharees ?? []) {
-      if (u != null && u.id != null && u.email.isNotEmpty) {
+    for (final User u in widget.collection.sharees) {
+      if (u.id != null && u.email.isNotEmpty) {
         existingEmails.add(u.email);
       }
     }
diff --git a/mobile/lib/ui/sharing/album_participants_page.dart b/mobile/lib/ui/sharing/album_participants_page.dart
index 656f9a0076..e27fe92478 100644
--- a/mobile/lib/ui/sharing/album_participants_page.dart
+++ b/mobile/lib/ui/sharing/album_participants_page.dart
@@ -64,11 +64,11 @@ class _AlbumParticipantsPageState extends State<AlbumParticipantsPage> {
   @override
   Widget build(BuildContext context) {
     final isOwner =
-        widget.collection.owner?.id == Configuration.instance.getUserID();
+        widget.collection.owner.id == Configuration.instance.getUserID();
     final colorScheme = getEnteColorScheme(context);
     final currentUserID = Configuration.instance.getUserID()!;
     final int participants = 1 + widget.collection.getSharees().length;
-    final User owner = widget.collection.owner!;
+    final User owner = widget.collection.owner;
     if (owner.id == currentUserID && owner.email == "") {
       owner.email = Configuration.instance.getEmail()!;
     }
@@ -107,11 +107,9 @@ class _AlbumParticipantsPageState extends State<AlbumParticipantsPage> {
                             captionedTextWidget: CaptionedTextWidget(
                               title: isOwner
                                   ? S.of(context).you
-                                  : widget.collection.owner != null
-                                      ? _nameIfAvailableElseEmail(
-                                          widget.collection.owner!,
-                                        )
-                                      : '',
+                                  : _nameIfAvailableElseEmail(
+                                      widget.collection.owner,
+                                    ),
                               makeTextBold: isOwner,
                             ),
                             leadingIconWidget: UserAvatarWidget(
diff --git a/mobile/lib/ui/sharing/manage_links_widget.dart b/mobile/lib/ui/sharing/manage_links_widget.dart
index 5b389fab82..6e55fbfbb9 100644
--- a/mobile/lib/ui/sharing/manage_links_widget.dart
+++ b/mobile/lib/ui/sharing/manage_links_widget.dart
@@ -47,13 +47,13 @@ class _ManageSharedLinkWidgetState extends State<ManageSharedLinkWidget> {
   @override
   Widget build(BuildContext context) {
     final isCollectEnabled =
-        widget.collection!.publicURLs?.firstOrNull?.enableCollect ?? false;
+        widget.collection!.publicURLs.firstOrNull?.enableCollect ?? false;
     final isDownloadEnabled =
-        widget.collection!.publicURLs?.firstOrNull?.enableDownload ?? true;
+        widget.collection!.publicURLs.firstOrNull?.enableDownload ?? true;
     final isPasswordEnabled =
-        widget.collection!.publicURLs?.firstOrNull?.passwordEnabled ?? false;
+        widget.collection!.publicURLs.firstOrNull?.passwordEnabled ?? false;
     final enteColorScheme = getEnteColorScheme(context);
-    final PublicURL url = widget.collection!.publicURLs!.firstOrNull!;
+    final PublicURL url = widget.collection!.publicURLs.firstOrNull!;
     final String collectionKey = Base58Encode(
       CollectionsService.instance.getCollectionKey(widget.collection!.id),
     );
diff --git a/mobile/lib/ui/sharing/pickers/device_limit_picker_page.dart b/mobile/lib/ui/sharing/pickers/device_limit_picker_page.dart
index 66c08bde74..3d83b4d8af 100644
--- a/mobile/lib/ui/sharing/pickers/device_limit_picker_page.dart
+++ b/mobile/lib/ui/sharing/pickers/device_limit_picker_page.dart
@@ -72,7 +72,7 @@ class _ItemsWidgetState extends State<ItemsWidget> {
   bool isCustomLimit = false;
   @override
   void initState() {
-    currentDeviceLimit = widget.collection.publicURLs!.first!.deviceLimit;
+    currentDeviceLimit = widget.collection.publicURLs.first.deviceLimit;
     initialDeviceLimit = currentDeviceLimit;
     if (!publicLinkDeviceLimits.contains(currentDeviceLimit)) {
       isCustomLimit = true;
diff --git a/mobile/lib/ui/sharing/share_collection_page.dart b/mobile/lib/ui/sharing/share_collection_page.dart
index 42ba9f417c..430935071a 100644
--- a/mobile/lib/ui/sharing/share_collection_page.dart
+++ b/mobile/lib/ui/sharing/share_collection_page.dart
@@ -61,7 +61,7 @@ class _ShareCollectionPageState extends State<ShareCollectionPage> {
 
   @override
   Widget build(BuildContext context) {
-    _sharees = widget.collection.sharees ?? [];
+    _sharees = widget.collection.sharees;
     final bool hasUrl = widget.collection.hasLink;
     final children = <Widget>[];
     children.add(
@@ -136,7 +136,7 @@ class _ShareCollectionPageState extends State<ShareCollectionPage> {
     }
 
     final bool hasExpired =
-        widget.collection.publicURLs?.firstOrNull?.isExpired ?? false;
+        widget.collection.publicURLs.firstOrNull?.isExpired ?? false;
     children.addAll([
       const SizedBox(
         height: 24,
@@ -166,7 +166,7 @@ class _ShareCollectionPageState extends State<ShareCollectionPage> {
           CollectionsService.instance.getCollectionKey(widget.collection.id),
         );
         final String url =
-            "${widget.collection.publicURLs!.first!.url}#$collectionKey";
+            "${widget.collection.publicURLs.first.url}#$collectionKey";
         children.addAll(
           [
             MenuItemWidget(
diff --git a/mobile/lib/ui/tabs/home_widget.dart b/mobile/lib/ui/tabs/home_widget.dart
index 0528c0d167..28165ddd4f 100644
--- a/mobile/lib/ui/tabs/home_widget.dart
+++ b/mobile/lib/ui/tabs/home_widget.dart
@@ -275,7 +275,7 @@ class _HomeWidgetState extends State<HomeWidget> {
       final existingCollection =
           CollectionsService.instance.getCollectionByID(collection.id);
 
-      if (collection.owner!.id! == Configuration.instance.getUserID() ||
+      if (collection.isOwner(Configuration.instance.getUserID() ?? -1) ||
           (existingCollection != null && !existingCollection.isDeleted)) {
         await routeToPage(
           context,
@@ -286,8 +286,8 @@ class _HomeWidgetState extends State<HomeWidget> {
         return;
       }
       final dialog = createProgressDialog(context, "Loading...");
-      final publicUrl = collection.publicURLs![0];
-      if (!publicUrl!.enableDownload) {
+      final publicUrl = collection.publicURLs[0];
+      if (!publicUrl.enableDownload) {
         await showErrorDialog(
           context,
           context.l10n.canNotOpenTitle,
diff --git a/mobile/lib/ui/tabs/shared/quick_link_album_item.dart b/mobile/lib/ui/tabs/shared/quick_link_album_item.dart
index 5c6b7c4c5f..db84df9083 100644
--- a/mobile/lib/ui/tabs/shared/quick_link_album_item.dart
+++ b/mobile/lib/ui/tabs/shared/quick_link_album_item.dart
@@ -109,7 +109,7 @@ class QuickLinkAlbumItem extends StatelessWidget {
                                     style: textTheme.smallMuted,
                                   ),
                                   c.hasLink
-                                      ? (c.publicURLs!.first!.isExpired
+                                      ? (c.publicURLs.first.isExpired
                                           ? Icon(
                                               Icons.link_outlined,
                                               color: colorScheme.warning500,
diff --git a/mobile/lib/ui/viewer/actions/file_selection_actions_widget.dart b/mobile/lib/ui/viewer/actions/file_selection_actions_widget.dart
index ab6cbf315a..97708bfbac 100644
--- a/mobile/lib/ui/viewer/actions/file_selection_actions_widget.dart
+++ b/mobile/lib/ui/viewer/actions/file_selection_actions_widget.dart
@@ -804,7 +804,7 @@ class _FileSelectionActionsWidgetState
             .getCollectionKey(_cachedCollectionForSharedLink!.id),
       );
       final String url =
-          "${_cachedCollectionForSharedLink!.publicURLs?.first?.url}#$collectionKey";
+          "${_cachedCollectionForSharedLink!.publicURLs.first.url}#$collectionKey";
       unawaited(Clipboard.setData(ClipboardData(text: url)));
       await shareImageAndUrl(
         placeholderBytes,
diff --git a/mobile/lib/ui/viewer/gallery/collect_photos_bottom_buttons.dart b/mobile/lib/ui/viewer/gallery/collect_photos_bottom_buttons.dart
index 5cb6f6c876..0d6b633040 100644
--- a/mobile/lib/ui/viewer/gallery/collect_photos_bottom_buttons.dart
+++ b/mobile/lib/ui/viewer/gallery/collect_photos_bottom_buttons.dart
@@ -48,7 +48,7 @@ class _EmptyAlbumStateNewState extends State<CollectPhotosBottomButtons> {
     final String collectionKey = Base58Encode(
       CollectionsService.instance.getCollectionKey(widget.c.id),
     );
-    final String url = "${widget.c.publicURLs!.first!.url}#$collectionKey";
+    final String url = "${widget.c.publicURLs.first.url}#$collectionKey";
     await shareAlbumLinkWithPlaceholder(
       context,
       widget.c,
diff --git a/mobile/lib/ui/viewer/gallery/gallery_app_bar_widget.dart b/mobile/lib/ui/viewer/gallery/gallery_app_bar_widget.dart
index d6ae1db26f..34c3c04b77 100644
--- a/mobile/lib/ui/viewer/gallery/gallery_app_bar_widget.dart
+++ b/mobile/lib/ui/viewer/gallery/gallery_app_bar_widget.dart
@@ -820,7 +820,7 @@ class _GalleryAppBarWidgetState extends State<GalleryAppBarWidget> {
           "Cannot share empty collection of type $galleryType",
         );
       }
-      if (Configuration.instance.getUserID() == widget.collection!.owner!.id) {
+      if (Configuration.instance.getUserID() == widget.collection!.owner.id) {
         unawaited(
           routeToPage(
             context,