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

Activity Tracking: Monitors steps, active minutes, sleep and distance. Tracks activities like running, biking, and sports. Has goal setting where kids can set daily step and activity goals. Movement reminder to encourage kids to stay active.
Family account: Parents can manage and view their child's activity.
Water resistant: Yes