New Balance 52537NB LifeTRNr Sync Fitness Heart Rate Monitor for iOS 7+ Data transmits via Bluetooth to New Balance Fitness App, Argus, MapMyRun, MapMyFitness, MapMyWalk and more. Requires iPhone 4S or newer with iOS 7+ installed.24 hour calorie burn algorithmOn demand heart rate touch reading is ECG accurate HRTPedometer step counterTime/Day/Date display Get fit the smart way with the New Balance LifeTRNr Sync Fitness Monitor Watch. Bluetooth Smart technology automatically transmits average heart rate, estimated calorie burn, total steps, distance traveled and total exercise time to a fitness app on your phone. LifeTRNr Sync also tracks your daily sleep habits and calculates 24-hour calorie burn (even when you're resting) for a big picture look at your health. The reversible band lets you