البطاريةFitness Tracker: Monitor your activity levels, sleep patterns, and more with Mi Band 2 which can record your steps, distance, pace, calories burned and active minutes, and sync its data via Bluetooth 4.0 to the Mi Fit app, Smart Reminder: When your phone receives calls, messages or other notifications such as from Facebook, Mi Band 2 will vibrate to remind you. Simply lift your arm to view the notification icon on the display screen with caller name/ID when you receive a call, IP67 Water-Resistant Wristband Watch: MI Band 2 is durable and resistant against water splashes, sweat, cosmetics, dust and more. You don’t need to worry when doing daily routines, even when washing hands or taking a shower, Compatibility: Support for Bluetooth 4.0 and above, Android 4.4 and above and iOS 7.1 and above iOS. Install MI Fit app to get instant statistics and set alarms, notification alerts, and other functions