Would also be interesting to know if the app looks at hrv data during a workout. For example it seems like it can be used to tell when someone passes certain thresholds like in:. https://www.ahajournals.org/doi/10.1161/JAHA.117.006612
Granted that means the app would need a database of heart rate straps that provide useful hrv data. (The identification info that ant and ble devices give that allow the app to give the name of the device) Not all heart rate straps give valid data like most optical sensors