diff --git a/mobile/lib/ui/viewer/gallery/component/group/type.dart b/mobile/lib/ui/viewer/gallery/component/group/type.dart
index f47156591..19b1224de 100644
--- a/mobile/lib/ui/viewer/gallery/component/group/type.dart
+++ b/mobile/lib/ui/viewer/gallery/component/group/type.dart
@@ -5,7 +5,14 @@ import "package:photos/generated/l10n.dart";
 import "package:photos/models/file/file.dart";
 import "package:photos/utils/date_time_util.dart";
 
-enum GroupType { day, week, month, size, year }
+enum GroupType {
+  day,
+  week,
+  month,
+  size,
+  year,
+  none,
+}
 
 extension GroupTypeExtension on GroupType {
   String get name {
@@ -20,9 +27,25 @@ extension GroupTypeExtension on GroupType {
         return "size";
       case GroupType.year:
         return "year";
+      case GroupType.none:
+        return "none";
     }
   }
 
+  bool timeGrouping() {
+    return this == GroupType.day ||
+        this == GroupType.week ||
+        this == GroupType.month ||
+        this == GroupType.year;
+  }
+
+  bool showGroupHeader() {
+    if (this == GroupType.size || this == GroupType.none) {
+      return false;
+    }
+    return true;
+  }
+
   String getTitle(BuildContext context, EnteFile file, {EnteFile? lastFile}) {
     if (this == GroupType.day) {
       return _getDayTitle(context, file.creationTime!);
@@ -41,7 +64,7 @@ extension GroupTypeExtension on GroupType {
       return DateFormat.yMMM(Localizations.localeOf(context).languageCode)
           .format(date);
     } else {
-      throw UnimplementedError("not implemented for $this");
+      throw UnimplementedError("getTitle not implemented for $this");
     }
   }
 
diff --git a/mobile/lib/ui/viewer/gallery/component/multiple_groups_gallery_view.dart b/mobile/lib/ui/viewer/gallery/component/multiple_groups_gallery_view.dart
index 094f915d3..e7ad53f46 100644
--- a/mobile/lib/ui/viewer/gallery/component/multiple_groups_gallery_view.dart
+++ b/mobile/lib/ui/viewer/gallery/component/multiple_groups_gallery_view.dart
@@ -9,7 +9,10 @@ import "package:photos/models/selected_files.dart";
 import "package:photos/ui/common/loading_widget.dart";
 import "package:photos/ui/huge_listview/huge_listview.dart";
 import 'package:photos/ui/viewer/gallery/component/group/lazy_group_gallery.dart';
+import "package:photos/ui/viewer/gallery/component/group/type.dart";
 import "package:photos/ui/viewer/gallery/gallery.dart";
+import "package:photos/ui/viewer/gallery/state/gallery_context_state.dart";
+import "package:photos/utils/data_util.dart";
 import "package:photos/utils/local_settings.dart";
 import "package:scrollable_positioned_list/scrollable_positioned_list.dart";
 
@@ -65,6 +68,7 @@ class MultipleGroupsGalleryView extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    final gType = GalleryContextState.of(context)!.type;
     return HugeListView<List<EnteFile>>(
       controller: itemScroller,
       startIndex: 0,
@@ -123,10 +127,17 @@ class MultipleGroupsGalleryView extends StatelessWidget {
       },
       labelTextBuilder: (int index) {
         try {
+          final EnteFile file = groupedFiles[index][0];
+          if (gType == GroupType.size) {
+            return file.fileSize != null
+                ? convertBytesToReadableFormat(file.fileSize!)
+                : "";
+          }
+
           return DateFormat.yMMM(Localizations.localeOf(context).languageCode)
               .format(
             DateTime.fromMicrosecondsSinceEpoch(
-              groupedFiles[index][0].creationTime!,
+              file.creationTime!,
             ),
           );
         } catch (e) {
diff --git a/mobile/lib/ui/viewer/gallery/gallery.dart b/mobile/lib/ui/viewer/gallery/gallery.dart
index 45a732ad0..b7edda271 100644
--- a/mobile/lib/ui/viewer/gallery/gallery.dart
+++ b/mobile/lib/ui/viewer/gallery/gallery.dart
@@ -214,7 +214,9 @@ class GalleryState extends State<Gallery> {
   // gallery reload
   bool _onFilesLoaded(List<EnteFile> files) {
     final updatedGroupedFiles =
-        widget.enableFileGrouping ? _groupFiles(files) : [files];
+        widget.enableFileGrouping && widget.groupType.timeGrouping()
+            ? _groupBasedOnTime(files)
+            : _genericGroupForPerf(files);
     if (currentGroupedFiles.length != updatedGroupedFiles.length ||
         currentGroupedFiles.isEmpty) {
       if (mounted) {
@@ -261,20 +263,52 @@ class GalleryState extends State<Gallery> {
         tagPrefix: widget.tagPrefix,
         scrollBottomSafeArea: widget.scrollBottomSafeArea,
         limitSelectionToOne: widget.limitSelectionToOne,
-        enableFileGrouping: widget.enableFileGrouping,
+        enableFileGrouping:
+            widget.enableFileGrouping && widget.groupType.showGroupHeader(),
         logTag: _logTag,
         logger: _logger,
         reloadEvent: widget.reloadEvent,
         header: widget.header,
         footer: widget.footer,
         selectedFiles: widget.selectedFiles,
-        showSelectAllByDefault: widget.showSelectAllByDefault,
+        showSelectAllByDefault:
+            widget.showSelectAllByDefault && widget.groupType.showGroupHeader(),
         isScrollablePositionedList: widget.isScrollablePositionedList,
       ),
     );
   }
 
-  List<List<EnteFile>> _groupFiles(List<EnteFile> files) {
+  // create groups of 200 files for performance
+  List<List<EnteFile>> _genericGroupForPerf(List<EnteFile> files) {
+    if (widget.groupType == GroupType.size) {
+      // sort files by fileSize on the bases of _sortOrderAsc
+      files.sort((a, b) {
+        if (_sortOrderAsc) {
+          return a.fileSize!.compareTo(b.fileSize!);
+        } else {
+          return b.fileSize!.compareTo(a.fileSize!);
+        }
+      });
+    }
+
+    final List<List<EnteFile>> resultGroupedFiles = [];
+    List<EnteFile> singleGroupFile = [];
+    const int groupSize = 40;
+    for (int i = 0; i < files.length; i += 1) {
+      singleGroupFile.add(files[i]);
+      if (singleGroupFile.length == groupSize) {
+        resultGroupedFiles.add(singleGroupFile);
+        singleGroupFile = [];
+      }
+    }
+    if (singleGroupFile.isNotEmpty) {
+      resultGroupedFiles.add(singleGroupFile);
+    }
+    _logger.info('Grouped files into ${resultGroupedFiles.length} groups');
+    return resultGroupedFiles;
+  }
+
+  List<List<EnteFile>> _groupBasedOnTime(List<EnteFile> files) {
     List<EnteFile> dailyFiles = [];
 
     final List<List<EnteFile>> resultGroupedFiles = [];