Only compatible with Android Smartphones (Runs on Wear OS Powered by Samsung) Bioelectrical Impedance Analysis Sensor for Body Composition Analysis, Optical Heart Rate Sensor. Health Monitoring features such as Advanced Sleep Analysis & Women's Health. Enhanced Fitness tracking lets you track 90+ workouts; Enriched App availability and connectivity with Wear OS, Powered by Samsung. Typical Usage Time (Hours): up to 40 Hours.