The Apple Watch Ultra 4 arrives three years after the Ultra 2. Across those two generations, Apple added satellite connectivity, a larger display, new health sensors, and longer battery life. Are those changes enough to justify replacing an Ultra 2 or paying more for the newest model?

Both watches retain a 49mm titanium case, an Action button, a siren, a 3,000-nit display, dual-frequency GPS, and support for recreational diving to 40 meters. The Apple Watch Ultra 4 starts at $799 in the U.S. Apple has discontinued the Ultra 2, although its refurbished store currently lists it from $589. Key differences include a 5% larger display, S11 chip, 4GB RAM, new Health Sensing System, 5G cellular, satellite connectivity, and up to 50 hours of normal use.

Most Apple Watch Ultra 2 owners should keep their watch if its battery still covers their usual days and workouts. The new Health Sensing System is the strongest reason to upgrade to an Ultra 4. It measures heart rate every five seconds and collects HRV data more frequently, enabling Recovery HRV, daytime Vitals, and the Readiness app. The S11 chip enables more accurate step counts, a Steps complication, and Audio Intelligence.

Satellite connectivity and longer battery life add further reasons to switch, especially for those who train or travel off-grid.