1. APP Support System: Android 4.4 and above, IOS above 9.0 2. Do not use a charger higher than 5V/2A. 3. The data cannot be used as medical reference. 4. The watch can't touch the hot water because the hot water would cause the watch display get fog. Model Number: D20 Pro Smart Watch APP: FitPro Bluetoth Version: Bluetooth 4.0 Waterproof / Water-Resistant: Yes(Not for swimming ) Operating mode: Touch button Power on: press and hold the function key Screen Type: 1.4 inch TFT LCD Storage(FLASH)16MB+128KB Compatible OS: Android,IOS Standby time: 4-7days normally use; 30 days standbybased on 230mAh.syi