Vahulawa TW64S Heart Rate Monitor Smart Band Smart watch Pulse Measure Smart Band Sport Smart Wristband Health Fitness Tracker Anti-lost for ios Android iphone Samsung (Dark Blue) System Compatiblity : IOS 7.1 / Android 4.4 or above/BLE 4.0 Main Functions:Heart Rate Monitor, Time Clock, Pedometer, Calories Counter, Distance Monitor , Sleep Monitor, Alarm Alert, Call Reminder, Anti-Lost,vibration alarm clock , Remote Camera Control. For Android Smartphones, it can support all the function in the description. For iOS iPhone, it cannot support call reminder, message reminder. When there is SMS, incoming call or message on the connected phone, the TW64S will alert you to read them. When the Bluetooth is disconnected or the phone is out of the Bluetooth distance, the watch will alert.