Apple Watch Ultra 4 Review: The Series 12 Is Closing the Gap

Not much has changed about the Apple Watch Ultra since its debut in 2022. The company’s heavy-duty smartwatch is still massive, titanium-clad, and equipped with enough emergency features to make one feel slightly more prepared for an apocalypse than the average Joe. Each generation has brought incremental improvements, but the Ultra has largely stuck to the formula, and this year’s release isn’t any different.

After testing both the Ultra 4 and the new Series 12, I noticed how little separates the two Apple Watches. The gap between them seems to shrink a little further every year, leaving fewer reasons to pay $799 for the beefier version. The Series 12 now shares many of the Ultra 4’s health and safety capabilities, and the Ultra’s biggest differentiators—its multiday battery, dedicated Action button, and satellite messaging—are more tailored to people who actually spend time off the grid.

This makes the Ultra 4 a more specialized smartwatch than ever, but also a tougher sell. Its benefits are clear for trail runners, divers, or anyone who regularly ventures outside cellular coverage. However, if your main goal is tracking health, workouts, and daily tasks, the Series 12 offers the same core experience for $400 less. And for current Ultra owners, the Ultra 4 serves as a reason to appreciate—and stick with—the generation you already have. Fortunately, there are no price changes, but there are no new finishes either.

Ready, Set, and Recover

The Ultra 4 gets the same new Health Sensing System as the Series 12, powered by Apple’s faster S11 chip and improved optical and electrical heart rate sensors. The system now tracks heart rate every five seconds throughout the day, and it measures heart rate variability (HRV) as often as every five minutes, which is up to 24 times more frequently than its predecessor. It also logs two HRV variants: Recovery HRV, which is intended to identify daily stressors, and overall HRV, which provides broader cardiovascular context.

While both of the new Apple Watches benefit from the higher-frequency tracking, it’s probably a more meaningful upgrade for people considering the Ultra as a fitness tracker. The Ultra 4 can now provide a more comprehensive picture of how your body is recovering and responding to stress throughout the day. Overnight Vitals now compares Recovery HRV against your personal baseline, and a new daytime view lets you look through differences between your day and overnight metrics.