This is a set of sport band. It is mainly concerned about the fitness and health of the population designed to help users understand their own health. Support what features: 1. sports statistics 2. sleep statistics 3. sport goal setting 4. calories calculate App support HealthKit application, you can view your data by health HealthKit App can be connected via Bluetooth hardware , downloads app, you can view the data by phone in the app, to help users better understand their physical condition and state of sleep. Note: Please wear the device to sleep, otherwise there is no accurate data