Apple Watch Ultra 4 Keeps Ultra 3 Design, Adds S11 Chip and New Health Sensors at $799

The watch runs on Apple's new S11 chip, a break from last year, when the company carried over the S10 introduced in 2024. Apple does not publish benchmark figures and describes the S11 only as its "most powerful wearable chip," saying the processor's added capability enables software features unavailable on earlier models. Memory doubles to 4GB from the 2GB in the Ultra 3.

Apple calls the Ultra 4's Health Sensing System possibly the biggest change yet to the watch's internal sensors, saying it "unlocks deeper health and fitness insights." A second-generation electrical heart sensor and an always-on optical heart sensor allow high-frequency background heart rate tracking, viewable through a new complication on the watch face. Heart rate variability is now measured up to 24 times more often and appears in a new section of the Heart Rate app, alongside a Recovery HRV reading intended to flag daily signals of stress and recovery. Step tracking is more accurate and gains a Steps complication that reports steps in real time from the watch face.

Battery life rises to 50 hours in normal use and 84 hours in Low Power Mode, compared with 42 and 72 hours for the Ultra 3. A 15-minute quick charge delivers 18 hours of runtime, 50 percent more than the 12 hours the Ultra 3 provides in the same period.

Two software features are exclusive to the new model. The Readiness app analyzes recent activity, training load, vitals and sleep score, then issues a single daily score from 0 to 10 with one of four recommendations: Recover, Pace Yourself, Ready or Go For It, meant to guide how a user approaches a workday or a training plan. Audio Intelligence covers Sound Recognition, which alerts deaf and hard-of-hearing users to sounds such as sirens, alarms, doorbells or a crying baby using on-device processing even when no iPhone is nearby; Live Rewind, which displays the previous 15 seconds of a conversation as text after a double press of the Digital Crown; Siri Recap, which generates a title and key points in the Siri app after a conversation; and Shazam, which identifies music playing nearby and posts the title and artist to the Music Recognition widget in the Smart Stack. Some of these features will arrive in a software update later this year.