Apple Watch Series 6 lets you measure your blood oxygen level with a revolutionary new sensor and app. Take an ECG from your wrist. See your fitness metrics on the enhanced Always-On Retina display, now 2.5x brighter outdoors when your wrist is down. Set a bedtime routine and track your sleep. And with cellular service, you can go without your phone.³ It's the ultimate device for a healthier, more active, more connected life.