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From N-Gine Innovation:
Great tool to calc your heart rate during a workout with a Bluetooth 4 HR sensor. Heart Rate Tracker allows to calculate an estimate of your maximum heart rate, and all heart rate training zones with your resting heart rate. You have a complete and accurate monitoring heart rate tool during your workout. Ideal to accompany a phase of loss or weighty control, work it split etc.Disclaimer : Continued use of Bluetooth link running in the background can dramatically decrease battery life.