No. The fasting timer, six-stage journey, journaling and break-fast guide all work without a wearable. A Garmin or Apple Watch adds live biometrics — heart rate, HRV, Body Battery, stress and SpO₂ — which drive the ring and power the AI Coach's personalized insights.
Tap Start Fast, choose a protocol (16:8, 20:4, OMAD, or custom), and confirm. The ring begins tracking immediately. To end a fast, press and hold End Fast — FastFlow will walk you through a short review and the break-fast guide.
16:8, 20:4, OMAD, and fully custom durations. You can also set an eating window and a weekly consistency goal during onboarding.
1. Install Garmin Connect Mobile on your iPhone and pair your watch with it.
2. Install the FastFlow watch app from the Garmin Connect IQ Store.
3. In FastFlow on iPhone, go to Settings → Connect wearable → Garmin and follow the prompts. Biometrics relay through Garmin Connect on your phone — nothing goes to our servers.
Go to Settings → Connect wearable → Apple Health and grant read access when prompted. You can review or revoke permissions anytime in the Health app under Sharing → Apps. FastFlow only reads metrics — it never writes to Health, and never uses Health data for anything except showing you your fast.
For Garmin: make sure Garmin Connect Mobile is running in the background, your watch is paired and in range, and the FastFlow watch app is installed and open at least once.
For Apple Watch: confirm Health permissions are granted and the watch has synced recently (open the Health app to force a sync).
Still stuck? Email us with your watch model and iOS version.
Live Garmin / Apple Watch biometric sync, full AI Coach insights, and your complete fasting history. Plans: $4.99/month, $39.99/year, or a one-time $79.99 lifetime purchase.
Subscriptions are handled entirely by Apple. On your iPhone, go to Settings → [your name] → Subscriptions → FastFlow to change or cancel. Cancelling takes effect at the end of the current billing period.
Open FastFlow, go to the Premium screen, and tap Restore Purchases. Make sure you're signed in with the same Apple ID you used to purchase.
On your device and in your own private iCloud. FastFlow has no account system and no servers that store your data. See our Privacy Policy for details.
Because everything lives on your device and in your iCloud, deleting the app and clearing its iCloud data (Settings → Apple ID → iCloud → Manage Storage) removes everything. There's no account to delete and nothing held on our side.
FastFlow provides general wellness information, not medical advice. Fasting isn't right for everyone — if you are pregnant, under 18, have a history of disordered eating, or manage a medical condition, talk with a healthcare professional first. FastFlow is designed around consistent, sustainable fasting and will never encourage extreme or unhealthy behavior.