Support

Gearstack supports Apple Watch Series 3 through Series 11, all SE generations and Ultra 1 to 3. For full functionality (ECG, SpO2, temperature) Series 6 or newer is recommended.

Analytics (CoreML) runs entirely on your iPhone. No health data leaves your device. Only the health coach (text answers) uses a cloud API, with vitals transmitted anonymously.

The Apple Watch uses PPG sensors with a typical deviation of ~17% compared to clinical ECG measurements. For higher accuracy we recommend the Gearstack X6 hardware (from Q4 2026).

Yes. The app also works with just the iPhone. You can enter vitals manually. For automatic tracking an Apple Watch is recommended.

Gearstack subscriptions are managed via the Apple App Store. Go to Settings → Apple ID → Subscriptions → Gearstack Health → Cancel. You keep access until the end of the billing period.