Devices Supported by FitNDev

Heart Rate Monitors

The FitNDev platform works with any heart rate monitor that supports Bluetooth Low Energy Standard 4.0 aka Bluetooth Smart. The following are the heart rate monitors that have been tested are known to work with the FitNDev system.


Supported Models: Zephyr HxM, both models for Android (HxM BT) and iOS (HxM Smart). The monitor transmits not only heart rate but RR-intervals and supports a skin contact monitoring feature.
Price Range: $45-$50

Known Issues

Contact pads are quite sensitive and even if the monitor reports that it has a good contact with the skin the heart rate measurements may not be accurate. This issue becomes especially noticeable when measuring HRV at rest and actual heart rate is in the range between 50 and 70 bpm but the monitor might at first report the values in the range of 100 bpm. This number will fall down to the actual range in 10-30 seconds but then might steadily climb up to above 200.
The resolve the issue moisten the contact pads of the monitor first.


Supported Models: CooSpo HRM H8. The monitor transmits heart rate only (no RR-intervals), nor does it support a skin contact monitoring feature.
Price Range: $25-$30

Known Issues

The sensor has inertia greater than any other tested monitors. Inertia here is defined as a time lag between a point when an actual heart rate changes and the point when the sensor detects it. The lag is about 10-15 seconds. For instance, if your heart rate goes up, the sensor will reflect this increase only at least 10 seconds later.