Specialized features, sensors, and three new bands designed for exploration, adventure, and endurance • 49mm aerospace-grade titanium case for an ideal balance of weight, strength, and corrosion resistance • The largest, brightest Apple Watch display for improved legibility in all conditions • Up to 36 hours of battery life for normal use along with low-power settings for even longer battery life1 • Precision dual-frequency GPS system provides accurate location for calculating distance, pace, and route maps • Water resistant 100m2 • Greater operating temperature tolerances while on-wrist to accommodate incredibly diverse environments • Customizable Action button can mark a Compass Waypoint, start Backtrack, mark segments in a workout, turn on the flashlight, and more • Advanced safety features, including Siren, Backtrack, Fall Detection, Emergency SOS3 ,and Crash Detection • Improved Workout app with new metrics, new views, and advanced ways to train • A completely redesigned Compass app with waypoints and Backtrack • Depth gauge and water temperature sensor activates automatically when you submerge • Made for recreational scuba diving and free diving down to 40 meters 4 • Included cellular lets you stay connected to people and information you care about most5 • Advanced health sensors let you take an ECG6and measure heart rate,track temperature changes7for insights into menstrual cycles, 8 and measure blood oxygen9 • Stream or sync your favorite music, podcasts, and audiobooks • Make purchases instantly and securely from your wrist with Apple Pay 10 • watchOS 9 features an enhanced Workout app, a new Medications app, sleep stages, and greater insights into heart health