Activity Tracking: Monitors steps, calories, distance, heart rate, sleep tracking, blood oxygen, stress tracking, GPS, energy levels, hydration and women’s health, body battery, readiness for workouts Tracks running, cycling, swimming, yoga, and other multi-sport tracking. Also has sports apps for workouts modes and guided exercises. Allows creating and customizing workouts.
Performance metrics: Provides VO2 max, training effect, and recovery time.
Maps: Includes preloaded topographic maps.
Notifications Displays notifications from your phone.
Water resistant: Yes

Activity Tracking: Monitors steps, calories, distance, heart rate, sleep, GPS, blood oxygen, fall detection. Supports a variety of workouts like running, cycling, yoga and swimming.
Temperature Sensor: Added on Series 8 and 9
Notifications: Displays notifications from your phone.
Water Resistant: Yes