With the largest and most advanced Always-On Retina Display to date, everything on your Apple Watch Series 7 is bigger and better. The Series 7 is the most durable Apple Watch ever developed, featuring even more shatter-resistant front glass. Measure the oxygen levels in your blood with advanced features, take an ECG anytime, and use apps for mindfulness and sleep tracking. Additionally, you can track dozens of workouts, including Tai Chi and Pilates.