Apple Watch Ultra 3 vs Ultra 4: What Actually Changed

The Apple Watch Ultra 4 looks identical to the Ultra 3 — same 49mm titanium case, same 3,000-nit display, same starting price — and puts the whole upgrade into endurance and sensors: up to 50 hours of battery, 84 in Low Power Mode, up to 18 hours of workout tracking, and the new Health Sensing System. It is the clearest single-purpose upgrade Apple has shipped in the Ultra line.

The battery numbers, side by side

• Normal use: up to 50 hours on the Ultra 4, up from 42 on the Ultra 3.
• Low Power Mode: up to 84 hours, up from 72.
• Workout tracking: up to 18 hours of continuous GPS, and a Max Extended mode rated at up to 45 hours for multi-day efforts.

Two full days with sleep tracking and workouts, without thinking about a charger, is now the normal case rather than the careful one. Apple's figures are on the Ultra 4 page.

What else is new?

The same S11 chip and redesigned Health Sensing System as the Series 12, which brings the Readiness score and more frequent background heart measurements, plus the Audio Intelligence features. Satellite features — Emergency SOS, Messages and Find My via satellite — continue from the Ultra 3.

What stayed the same?

Everything you can see: the 49mm titanium case in natural and black, the wide-angle display at up to 3,000 nits, the Action Button, the bands, dual-frequency GPS and the 100m water rating. And the price.

Should you upgrade from an Ultra 3?

Only if the extra battery is the feature you have been missing — ultrarunners, expedition hikers and anyone who resents the charger will feel the difference; everyone else will not. From an Ultra 2 or the original Ultra, you gain satellite messaging, the brighter display and two sensor generations on top of the battery, and the case is much stronger.

Q: Is the Apple Watch Ultra 4 bigger than the Ultra 3?
A: No. Same 49mm titanium case; the weight difference is about a gram.

Q: How much longer does the Ultra 4 battery last?
A: Apple rates it at up to 50 hours against 42 for the Ultra 3, and 84 against 72 in Low Power Mode.

Q: Does the Ultra 4 cost more?
A: No, it launched at the same $799 starting price.

Q: Does the Ultra 3 get the new watchOS features?
A: It gets watchOS itself, but the Readiness score and Audio Intelligence depend on the Ultra 4's new sensors and S11 chip.

However long your battery lasts, the iWatchly apps work the same on every Ultra.