Allow calls via Bluetooth Compatible systems include iOS 8.0 and higher and Android 4.4 and higher. APP: SZOS FLASH memory: 192KB of RAM Full-fitting 1.85-inch screen size HD 240*280 pixels Full touch screen is the type of touch. The polymer battery has a 190mAh capacity and takes 150 minutes to fully charge. Wireless charging is the method of charging. Composition: silicone wristband Take calls, send and receive texts, and enjoy music. The APP sleep interface allows you to view the day's sleep history and details. This product is rain-resistant, IP68 waterproof, and hand-washing compatible. Receive alerts before your heart rate becomes too high or too low. Keep track of how much you exercise each day and precisely adhere to standard physical training regimens.