AMOLED screen, 1.62 inches, with a pixel resolution and brightness of up to 500 nits. Xiaomi 180mAh battery lasts up to approximately 14 days with normal use. More than 110 sports modes for exercise tracking. All-day heart rate monitoring. Blood oxygen saturation (SpO2) measurement. Sleep, stress, and breathing tracking. Water-resistant up to 5 ATM (suitable for swimming). Supports Android and iPhone via the Mi Fitness app.