diff --git a/accounts/sync.py b/accounts/sync.py
index dcd2422..5dccfb3 100644
--- a/accounts/sync.py
+++ b/accounts/sync.py
@@ -19,7 +19,11 @@ def sync_snapshot(request):
     endpoints (e.g. GET /books/<id>/data/), which this same token also
     unlocks. Writes (progress, highlights, bookmarks, ...) go through those
     existing endpoints too, to reuse their merge semantics rather than
-    duplicating it here."""
+    duplicating it here.
+
+    ?only=books: just the books' part. The apps' book sync needs nothing else,
+    and the podcast part is by far the biggest (every episode ever played:
+    megabytes for an account that moved over from AntennaPod)."""
     if not request.user.is_authenticated:
         return JsonResponse({'error': 'authentication required'}, status=401)
 
@@ -43,6 +47,15 @@ def sync_snapshot(request):
     for bm in book_bookmarks:
         bm['updated_at'] = bm['updated_at'].isoformat()
 
+    if request.GET.get('only') == 'books':
+        return JsonResponse({
+            'server_time': timezone.now().isoformat(),
+            'books': books,
+            'book_progress': book_progress,
+            'book_highlights': book_highlights,
+            'book_bookmarks': book_bookmarks,
+        })
+
     podcast_feeds = list(
         PodcastFeed.objects.filter(user=user)
         .annotate(latest_episode_at=Max('episodes__pub_date'))
diff --git a/accounts/tests.py b/accounts/tests.py
index 638ec51..35d015e 100644
--- a/accounts/tests.py
+++ b/accounts/tests.py
@@ -85,6 +85,12 @@ class SyncSnapshotTests(TestCase):
         resp = self.client.get('/api/sync/')
         self.assertEqual(resp.status_code, 401)
 
+    def test_only_books(self):
+        resp = self.client.get('/api/sync/?only=books', HTTP_AUTHORIZATION=f'Bearer {self.token.token}')
+        data = resp.json()
+        self.assertEqual(set(data), {'server_time', 'books', 'book_progress', 'book_highlights', 'book_bookmarks'})
+        self.assertEqual(data['book_highlights'][0]['ct'], 'hl-ct')
+
     def test_snapshot_shape_and_data(self):
         resp = self.client.get('/api/sync/', HTTP_AUTHORIZATION=f'Bearer {self.token.token}')
         self.assertEqual(resp.status_code, 200)