diff --git a/lib/widgets/album/collection_app_bar.dart b/lib/widgets/album/app_bar.dart
similarity index 100%
rename from lib/widgets/album/collection_app_bar.dart
rename to lib/widgets/album/app_bar.dart
diff --git a/lib/widgets/album/collection_section.dart b/lib/widgets/album/collection_section.dart
deleted file mode 100644
index 1c3732ea3..000000000
--- a/lib/widgets/album/collection_section.dart
+++ /dev/null
@@ -1,60 +0,0 @@
-import 'package:aves/model/collection_lens.dart';
-import 'package:aves/model/image_entry.dart';
-import 'package:aves/widgets/album/grid/header_album.dart';
-import 'package:aves/widgets/album/thumbnail.dart';
-import 'package:aves/widgets/album/transparent_material_page_route.dart';
-import 'package:aves/widgets/fullscreen/fullscreen_page.dart';
-import 'package:flutter/material.dart';
-
-class GridThumbnail extends StatelessWidget {
-  final CollectionLens collection;
-  final int index;
-  final ImageEntry entry;
-  final double tileExtent;
-  final GestureTapCallback onTap;
-
-  const GridThumbnail({
-    Key key,
-    this.collection,
-    this.index,
-    this.entry,
-    this.tileExtent,
-    this.onTap,
-  }) : super(key: key);
-
-  @override
-  Widget build(BuildContext context) {
-    return GestureDetector(
-      key: ValueKey(entry.uri),
-      onTap: () => _goToFullscreen(context),
-      child: MetaData(
-        metaData: ThumbnailMetadata(index, entry),
-        child: Thumbnail(
-          entry: entry,
-          extent: tileExtent,
-          heroTag: collection.heroTag(entry),
-        ),
-      ),
-    );
-  }
-
-  void _goToFullscreen(BuildContext context) {
-    Navigator.push(
-      context,
-      TransparentMaterialPageRoute(
-        pageBuilder: (c, a, sa) => MultiFullscreenPage(
-          collection: collection,
-          initialEntry: entry,
-        ),
-      ),
-    );
-  }
-}
-
-// metadata to identify entry from RenderObject hit test during collection scaling
-class ThumbnailMetadata {
-  final int index;
-  final ImageEntry entry;
-
-  const ThumbnailMetadata(this.index, this.entry);
-}
diff --git a/lib/labs/sliver_known_extent_list.dart b/lib/widgets/album/grid/list_known_extent.dart
similarity index 99%
rename from lib/labs/sliver_known_extent_list.dart
rename to lib/widgets/album/grid/list_known_extent.dart
index 769ade9b2..21b75b769 100644
--- a/lib/labs/sliver_known_extent_list.dart
+++ b/lib/widgets/album/grid/list_known_extent.dart
@@ -1,6 +1,6 @@
 import 'dart:math' as math;
 
-import 'package:aves/widgets/album/collection_list_sliver.dart';
+import 'package:aves/widgets/album/grid/list_section_layout.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/widgets.dart';
diff --git a/lib/widgets/album/grid/list_section_layout.dart b/lib/widgets/album/grid/list_section_layout.dart
new file mode 100644
index 000000000..0292397d2
--- /dev/null
+++ b/lib/widgets/album/grid/list_section_layout.dart
@@ -0,0 +1,42 @@
+import 'package:flutter/material.dart';
+
+class SectionLayout {
+  final dynamic sectionKey;
+  final int firstIndex, lastIndex;
+  final double minOffset, maxOffset;
+  final double headerExtent, tileExtent;
+  final IndexedWidgetBuilder builder;
+
+  const SectionLayout({
+    @required this.sectionKey,
+    @required this.firstIndex,
+    @required this.lastIndex,
+    @required this.minOffset,
+    @required this.maxOffset,
+    @required this.headerExtent,
+    @required this.tileExtent,
+    @required this.builder,
+  });
+
+  bool hasChild(int index) => firstIndex <= index && index <= lastIndex;
+
+  bool hasChildAtOffset(double scrollOffset) => minOffset <= scrollOffset && scrollOffset <= maxOffset;
+
+  double indexToLayoutOffset(int index) {
+    return minOffset + (index == firstIndex ? 0 : headerExtent + (index - firstIndex - 1) * tileExtent);
+  }
+
+  double indexToMaxScrollOffset(int index) {
+    return minOffset + headerExtent + (index - firstIndex) * tileExtent;
+  }
+
+  int getMinChildIndexForScrollOffset(double scrollOffset) {
+    scrollOffset -= minOffset + headerExtent;
+    return firstIndex + (scrollOffset < 0 ? 0 : (scrollOffset / tileExtent).floor());
+  }
+
+  int getMaxChildIndexForScrollOffset(double scrollOffset) {
+    scrollOffset -= minOffset + headerExtent;
+    return firstIndex + (scrollOffset < 0 ? 0 : (scrollOffset / tileExtent).ceil() - 1);
+  }
+}
diff --git a/lib/widgets/album/collection_list_sliver.dart b/lib/widgets/album/grid/list_sliver.dart
similarity index 71%
rename from lib/widgets/album/collection_list_sliver.dart
rename to lib/widgets/album/grid/list_sliver.dart
index daf365409..3cb88f5bf 100644
--- a/lib/widgets/album/collection_list_sliver.dart
+++ b/lib/widgets/album/grid/list_sliver.dart
@@ -1,9 +1,13 @@
 import 'dart:math';
 
-import 'package:aves/labs/sliver_known_extent_list.dart';
 import 'package:aves/model/collection_lens.dart';
-import 'package:aves/widgets/album/collection_section.dart';
+import 'package:aves/model/image_entry.dart';
 import 'package:aves/widgets/album/grid/header_generic.dart';
+import 'package:aves/widgets/album/grid/list_known_extent.dart';
+import 'package:aves/widgets/album/grid/list_section_layout.dart';
+import 'package:aves/widgets/album/thumbnail.dart';
+import 'package:aves/widgets/album/transparent_material_page_route.dart';
+import 'package:aves/widgets/fullscreen/fullscreen_page.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
 
@@ -106,43 +110,55 @@ class CollectionListSliver extends StatelessWidget {
   }
 }
 
-class SectionLayout {
-  final dynamic sectionKey;
-  final int firstIndex, lastIndex;
-  final double minOffset, maxOffset;
-  final double headerExtent, tileExtent;
-  final IndexedWidgetBuilder builder;
+class GridThumbnail extends StatelessWidget {
+  final CollectionLens collection;
+  final int index;
+  final ImageEntry entry;
+  final double tileExtent;
+  final GestureTapCallback onTap;
 
-  const SectionLayout({
-    @required this.sectionKey,
-    @required this.firstIndex,
-    @required this.lastIndex,
-    @required this.minOffset,
-    @required this.maxOffset,
-    @required this.headerExtent,
-    @required this.tileExtent,
-    @required this.builder,
-  });
+  const GridThumbnail({
+    Key key,
+    this.collection,
+    this.index,
+    this.entry,
+    this.tileExtent,
+    this.onTap,
+  }) : super(key: key);
 
-  bool hasChild(int index) => firstIndex <= index && index <= lastIndex;
-
-  bool hasChildAtOffset(double scrollOffset) => minOffset <= scrollOffset && scrollOffset <= maxOffset;
-
-  double indexToLayoutOffset(int index) {
-    return minOffset + (index == firstIndex ? 0 : headerExtent + (index - firstIndex - 1) * tileExtent);
+  @override
+  Widget build(BuildContext context) {
+    return GestureDetector(
+      key: ValueKey(entry.uri),
+      onTap: () => _goToFullscreen(context),
+      child: MetaData(
+        metaData: ThumbnailMetadata(index, entry),
+        child: Thumbnail(
+          entry: entry,
+          extent: tileExtent,
+          heroTag: collection.heroTag(entry),
+        ),
+      ),
+    );
   }
 
-  double indexToMaxScrollOffset(int index) {
-    return minOffset + headerExtent + (index - firstIndex) * tileExtent;
-  }
-
-  int getMinChildIndexForScrollOffset(double scrollOffset) {
-    scrollOffset -= minOffset + headerExtent;
-    return firstIndex + (scrollOffset < 0 ? 0 : (scrollOffset / tileExtent).floor());
-  }
-
-  int getMaxChildIndexForScrollOffset(double scrollOffset) {
-    scrollOffset -= minOffset + headerExtent;
-    return firstIndex + (scrollOffset < 0 ? 0 : (scrollOffset / tileExtent).ceil() - 1);
+  void _goToFullscreen(BuildContext context) {
+    Navigator.push(
+      context,
+      TransparentMaterialPageRoute(
+        pageBuilder: (c, a, sa) => MultiFullscreenPage(
+          collection: collection,
+          initialEntry: entry,
+        ),
+      ),
+    );
   }
 }
+
+// metadata to identify entry from RenderObject hit test during collection scaling
+class ThumbnailMetadata {
+  final int index;
+  final ImageEntry entry;
+
+  const ThumbnailMetadata(this.index, this.entry);
+}
diff --git a/lib/widgets/album/grid/scaling.dart b/lib/widgets/album/grid/scaling.dart
index cc90ac6c9..a1908573f 100644
--- a/lib/widgets/album/grid/scaling.dart
+++ b/lib/widgets/album/grid/scaling.dart
@@ -2,7 +2,7 @@ import 'dart:math';
 import 'dart:ui' as ui;
 
 import 'package:aves/model/image_entry.dart';
-import 'package:aves/widgets/album/collection_section.dart';
+import 'package:aves/widgets/album/grid/list_sliver.dart';
 import 'package:aves/widgets/album/thumbnail.dart';
 import 'package:aves/widgets/album/tile_extent_manager.dart';
 import 'package:aves/widgets/common/data_providers/media_query_data_provider.dart';
diff --git a/lib/widgets/album/thumbnail_collection.dart b/lib/widgets/album/thumbnail_collection.dart
index bd98a5735..dd61e1481 100644
--- a/lib/widgets/album/thumbnail_collection.dart
+++ b/lib/widgets/album/thumbnail_collection.dart
@@ -2,10 +2,10 @@ import 'package:aves/model/collection_lens.dart';
 import 'package:aves/model/filters/favourite.dart';
 import 'package:aves/model/filters/mime.dart';
 import 'package:aves/model/mime_types.dart';
-import 'package:aves/widgets/album/collection_app_bar.dart';
-import 'package:aves/widgets/album/collection_list_sliver.dart';
+import 'package:aves/widgets/album/app_bar.dart';
 import 'package:aves/widgets/album/collection_page.dart';
 import 'package:aves/widgets/album/empty.dart';
+import 'package:aves/widgets/album/grid/list_sliver.dart';
 import 'package:aves/widgets/album/grid/scaling.dart';
 import 'package:aves/widgets/album/tile_extent_manager.dart';
 import 'package:aves/widgets/common/scroll_thumb.dart';