PRIVACY POLICY
Privacy
Last updated 2026-04-25
Tillen is built offline-first. Your training data lives in a local SQLite database on your phone and is not sent anywhere unless you explicitly turn on a sync or backup destination.
Local data
The Tillen app stores workouts, exercises, templates, body measurements, and your settings on your device. None of this is transmitted to Tillen servers by default. Uninstalling the app deletes the local database.
Backup destinations
If you turn on auto-backup, Tillen writes encrypted .tillen
files to the destination you pick: a folder on your device, your
Google Drive (App Folder, scope drive.file),
iCloud (iOS), or Tillen Sync (closed beta). The files are
encrypted client-side with Argon2id + AES-GCM-256 using your
passphrase. We never see the passphrase or the plaintext data.
Tillen Sync
Tillen Sync stores the same encrypted .tillen
blobs in Cloudflare R2 (object storage). The server has no key
and cannot read the contents. The members portal at members.tillen.app
downloads the blob, asks you for the passphrase, and decrypts
in your browser. If you forget your passphrase, your data is
unrecoverable — there is no reset.
Account data
If you sign up for Tillen Sync, we store your email address and a session token, both in Cloudflare D1 (a managed SQLite database). Sessions live for 30 days and can be revoked from the members portal Settings page. You can delete your account and all uploaded blobs at any time from the same page; the deletion runs server-side and cascades to R2.
Health Connect (Android)
If you grant Health Connect permission, Tillen writes completed-workout records (exercise session + active calories) to the Health Connect store on your device. We never read from Health Connect, and the records are managed by the system Health Connect app. You can revoke permission at any time in Health Connect.
Analytics
Tillen does not embed third-party analytics, tracking pixels, advertising SDKs, or fingerprinting libraries. The website you are reading is statically hosted on Cloudflare Pages, which records aggregate request metadata for security and uptime.
Children
Tillen is not directed at children under 13. If you believe a child has provided personal information to us, please contact us so we can remove it.
Contact
Questions or data requests: [email protected].
This page is a starting structure. Final legal text is pending review before launch.