Support

Something not working, or a number looks off? Write to contact@knowyourlimits.fit. A screenshot and the matching line from More → Sync log help us fix it fast.

Frequently asked questions

What do I need to use the app?

An iPhone on iOS 17 or later and a Fitbit Air paired with the Google Health app.

Why does it say “calibrating”?

Metrics are compared with your own baseline. Recovery needs about 5 nights; biological age needs 14 to 30 days of data.

Where is my data?

Only on your iPhone. We have no servers. More in the privacy policy.

How do I delete my data?

More → Delete all data, or uninstall the app. To revoke Google access, go to myaccount.google.com/permissions.

Is it a medical device?

No. The metrics are for information only and do not replace advice from a health professional.