Health Sync is a free iPhone application designed to facilitate the synchronization of health data between various fitness apps. Currently in its early access phase, the app supports syncing between Apple Health, Huawei Health, Garmin Connect, and Fitbit, with additional apps planned for future updates. Users can sync real-time data from the moment they start using the app, while historical data can be synced after the initial one-week free trial. Notably, Garmin users can sync up to five years of activity data and two years of other health metrics.

The app runs background sync processes a few times per hour, although syncing from Apple Health requires the phone to be unlocked. Health Sync is user-friendly and prioritizes privacy by processing all data locally on the device. Users can also access a Help Center for troubleshooting, ensuring that most synchronization issues can be resolved quickly. After the trial period, a one-time purchase provides a lifetime license and access to historical data syncing.