Mueff / Privacy
Privacy.
Short version: your data stays on your iPhone and Apple Watch. Mueff has no account, no tracking and no ads.
What stays on your device
Your settings (time, gear, level, age if you type it), the workouts you pin and the record of what you've done are stored in the app on your iPhone. They are not sent to us or anyone else.
Apple Health
With your permission, Mueff reads your workouts and exercise minutes (so Today can start from what you already did), your heart rate (to show it on your Watch) and your date of birth (to fit workouts to your age). It saves the workouts you finish. Health data is read and written on your device through Apple's HealthKit and is never sent to us, sold, or used for advertising.
Purchases
Mueff+ is bought through Apple. We don't see your payment details.
Sharing
When you share a workout card, you choose the app and the people. Nothing is shared without your tap.
This website
mueff.com sets no cookies and runs no analytics.
Contact
support@mueff.com. Updated 6 November 2026.