smart watch sports fitness activity heart rate watch

feature: fully compatible with various smartphones (android and apple's ios system) compatile for system: ios 7.0 and later, andorid 4.0 and later. multi-functional fitness tracker: accurately track your steps, distance, calories burnt, sleep quality and heart rate all day. the smart band will vibrate in specific time to avoid harmful effect of sedentary, then reminds you to take some exercise. when you answer the phone or receive a text message, the smart hand ring will vibrate t...