Apple Watch Ultra 4 has the same external look as Ultra 3, but it’s packed with internal upgrades to the chip and health sensors that unlock new and improved features.

S11 chip and 4GB RAM boost performance. Apple Watch Ultra 4 has a brand-new S11 chip, unlocking exclusive software features. It doubles memory to 4GB versus 2GB.

An all-new Health Sensing System enables high-frequency background heart rate tracking, HRV measured up to 24 times more often, new Recovery HRV, and more accurate step tracking. Battery life improves to up to 50 hours (84 in Low Power Mode) from 42 hours (72). A 15-minute charge gives 18 hours, versus 12.

Exclusive software includes a Readiness app with a 0-10 score and Audio Intelligence: Sound Recognition, Live Rewind, Siri Recap, and Shazam.