Privacy policy

Last updated: October 25, 2026

Stumbler is an Android app for browsing images on Tumblr and other sites. This policy explains what it handles, where that goes and what you can do about it. Stumbler is operated by Brilliance Mobility ("we").

On your phone

• Your Tumblr sign-in. When you sign in, Tumblr gives the app an access token, which is kept on your phone. We never see your Tumblr password.
• Bookmarks, history, favorites and likes: the blogs you save, the blogs you visit, the photos you mark and the posts you like.
• Photos you download, saved to your phone's Pictures folder.
• Settings and recent searches.

Searching your own bookmarks, history and likes, and our curated lists, happens on your phone; those searches are not sent anywhere.

What the app sends to other services

• Tumblr receives your requests to browse, search tags, like, follow, reblog and post, under your Tumblr account when you are signed in. Tumblr's own privacy policy applies.
• Flickr, Imgur, Bluesky and Openverse receive what you type when you search them, and the images you view come from their servers.
• Google Lens receives a photo only when you choose "Search by image".
• Your phone's photo editor receives a photo only when you choose to edit or remix it.

What our servers keep

• Your Tumblr identity. To use sync or upload staging, the app sends its Tumblr access token to our server once per sign-in, and we ask Tumblr who it belongs to. We keep your primary blog's identifier and your username, not the token.
• Sync (optional). If you turn on sync, we store your bookmarks, history and favorites, linked to that identifier, so they appear on your other phones. We keep them until you delete them or ask us to delete your data.
• Uploads. If a photo upload to Tumblr fails, the app may store the photo on our servers briefly so Tumblr can fetch it from there. These copies are deleted within a day.
• Server logs (request time, address and errors), kept for 30 days to keep the service running.
• Email you send us, kept for 90 days.

The app's home feed and curated lists are downloaded from our website; that request carries no account information.

What we don't do

• No advertising and no advertising identifiers.
• No selling or sharing of your data.
• No analytics or tracking SDKs in the app.

Your choices

• Stumbler works without sync. Sync is off until you turn it on.
• You can clear your history and bookmarks in the app, and uninstalling the app removes everything it stored on your phone except photos you downloaded.
• To delete the data we keep, see Delete your data.

Children

Stumbler is not directed at children under 13, and Tumblr requires its users to be at least 13.

Changes and contact

We will post changes here and update the date above. Questions: privacy@getstumbler.com.