Apple Watch Apple Watch Ultra 3 Display Technical Specifications Always-On Retina LTPO3 OLED display with ProMotion technology 1Hz refresh rate Actual screen area 422 × 514 pixels, 326 pixels per inch) Flat sapphire crystal front Up to 3000 nits peak brightness 1 nit minimum brightness Night mode for Apple Watch Ultra watch faces (Modular Ultra, Wayfinder, and Compass) Chip S10 chip with 64-bit dual-core processor 4-core Neural Engine 64GB capacity Health and Wellness Blood Oxygen app ECG app Cycle Tracking app with retrospective ovulation estimates Heart Rate app High heart rate and low heart rate notifications Irregular rhythm notifications Medications app Mindfulness app with mood tracking Noise app Sleep app including sleep stages Safety and Emergency SOS emergency feature, worldwide emergency calls, siren, flashlight, crash detection Fall detection feature, last available waypoint for emergency calls, noise monitoring Compass Compass, always-on altimeter, accelerometer with high-g, gyroscope with high dynamic range Ambient light sensor Audio Array of three microphones with beamforming technology and wind noise reduction, dual speakers