Privacy policy

Last updated: 7 September 2026

Who publishes STARK

STARK is published by Axel Saillard, sole trader under the French micro-entrepreneur scheme, 10 rue Dupuy, 16100 Cognac, France. SIREN 104005749, SIRET 10400574900015, APE code 6201Z. Publication manager: Axel Saillard.

What we collect

Only what you enter: your email address, your workouts (exercises, sets, weights, reps, notes), your workout templates, your body weight if you record it, your progress photos if you add any, and — if you use the social features — your nickname, your comments and your program ratings. STARK also records app crash and performance reports, through Sentry, with no identity attached.

The app can be used without an account. In guest mode an anonymous account is created automatically: the data does live on the server, but it is tied to that device alone — uninstall the app and it can no longer be recovered.

If you start a cardio outing with GPS and allow location access, STARK uses your precise location during that outing, including while the screen is locked, to calculate distance, pace and your route. The route is saved with your workout on your device and on Supabase, linked to your account. It is not shared with friends. You can revoke access in iOS Settings and delete the route by deleting the workout or your account.

Apple Health

With your permission, STARK reads your body weight, heart rate, steps, sleep and the calories recorded by your other apps from Apple Health, to put your progress in context. It writes one thing only: your completed workouts.

Health data is never used for advertising or marketing, never sold, and never shared with third parties or data brokers. It is used solely to run the features described above. Permission is asked the first time a feature actually needs it, and can be withdrawn at any time in the iOS Health app.

What other users can see

Nothing is public by default. If you accept a friend, that friend sees your completed workouts and their exercises and sets, your nickname, and the emoji and comments left on them. Ratings you leave on STARK programs are visible to everyone who opens that program.

Any workout, comment, rating or account published by someone else can be reported and blocked from the app. Blocking cuts visibility both ways and removes that account from program ratings. Reports are reviewed manually.

Where the data lives

On Supabase, Inc., which hosts the database, authentication and photo storage as our processor. Purchases are handled by Apple and by RevenueCat, which tells us whether a subscription is active — no payment details ever reach us. Crash and performance reports go to Sentry as our processor. Display preferences (theme, colour, language, usual gym) stay on your device and are never sent.

What we don't do

No advertising, no trackers, no analytics profiling, no sale of data, no sharing with advertisers or data brokers. The crash reports mentioned above carry no advertising identifier, are not linked to your account and are used only to fix bugs. The app does not read your address book or contacts.

Your rights

You can export your workouts and templates as JSON at any time (Profile → Account settings → Data), delete your workouts, or delete your account from inside the app. Deleting your account removes the account, the workouts, the templates and the associated photos, with no copy kept. You can also ask for access, correction, erasure or portability by email.

Notifications

The rest timer and training reminders use local notifications calculated on the device. Friend-workout notifications are also local, but are triggered when the app refreshes activity from the server. Permission can be withdrawn at any time in iOS Settings.

Changes

This policy may change with new versions of the app. The date at the top of this page indicates the version in force.

Contact

Questions about your data, or a report about content? Email contact@starkworkout.app.

The terms of use are available from the STARK website.

The JSON export includes your workouts, templates and email address. Programs, weigh-ins, photos and preferences are not included.

Personal notes, post-workout feedback and GPS routes remain private to your account.