BitGym supports Bluetooth Smart heart rate monitors. These are also known as BT 4.0 or BT Low Energy devices.
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Garmin and Polar watches often will broadcast HRM over bluetooth, such that BitGym can be paired with them, although it will vary by model.
Android Wear and Samsung Galaxy watches can be modified to broadcast HRM with the help of a third party app running on them enabling that functionality.
Apple Watch does not broadcast HRM to third party apps, however there are work arounds. One option is to purchase the HeartBeatz device ($40 USD), which can wirelessly connect to your Apple Watch, read your heart rate, and re-broadcast it as a standard bluetooth signal to apps such as BitGym.
Please note BitGym does not support any ANT+ devices. FitBit devices also do not work with third party apps, and so will not connect to BitGym. You can still use your FitBit to train, but the data won't be linked into our app.
See our article on how to connect your heart rate monitor for more info.