Hands-on review: Apple Watch Ultra 4 adds staying power

Apple Watch Ultra 4 makes its strongest case through longer battery life and a clearer picture of recovery. Its redesigned health sensors collect more frequent readings. A new readiness score gives that information a more accessible purpose.

The changes improve an already capable smartwatch, although they do little to address its size. The Ultra remains a substantial watch with a substantial price. At AUD $1,349 / NZD $1,599 including GST, its appeal depends on how much you value endurance and outdoor features.

Familiar shape

The 49mm titanium case comes in natural and black finishes. Its flat sapphire crystal and prominent crown retain the Ultra's recognisable appearance. There is still no smaller version.

That matters for a watch designed to collect information around the clock. Smaller wrists may find the case cumbersome, particularly in bed. A secure fit also matters for reliable heart rate readings. The adjustable Trail Loop is a sensible choice for daily wear and quick adjustments during exercise.

The orange Action button remains one of the design's most useful features. It provides a physical shortcut to functions such as starting a workout. Touchscreen controls can become frustrating with sweaty fingers, so the button earns its place. More functions still require taps and swipes than some athletes would prefer.

The always-on display reaches a claimed peak brightness of 3,000 nits. Its generous viewing area makes workout data easier to read at a glance. Existing Ultra 3 owners will find little reason to upgrade for the screen alone.

Health tracking

The most significant hardware change sits against your skin. Apple has redesigned the optical and electrical sensors, pairing them with the new S11 chip.

Background heart rate readings now arrive every five seconds. Previous models attempted a reading every five minutes and generally required relative stillness. The Ultra 4 can continue taking readings while you move. A live heart rate complication makes those measurements visible without opening an app.

Heart rate variability, or HRV, measures changes in the time between heartbeats. The watch can sample it as often as every five minutes while you are at rest. Recovery HRV focuses on signals associated with daily stress and fatigue. A separate overall HRV measure provides broader health context.

These additions make the data more useful between workouts. Overnight Vitals now includes Recovery HRV against your personal baseline. A daytime view adds heart rate and HRV information, helping you spot changes before the following morning.

More frequent measurements do not make every reading definitive. Fit and movement still affect wrist sensing. Vitals provides wellness information rather than a medical assessment.

Recovery check

Readiness is the clearest expression of the new sensors' purpose. It combines recent activity, training load, sleep score and vitals into a score from zero to 10. Recommendations range from Recover to Go For It.

The score updates during the day as activity and other measurements change. It also explains which factors raised or lowered the result. That is more useful than presenting a number without context.

You need an initial baseline of seven nights before receiving a score. Consistent overnight wear therefore becomes part of the routine. The watch's size may make that commitment less comfortable for some people.

Readiness also has room to improve. Its lack of a conventional score history makes it harder to review patterns across a week. Keeping Readiness separate from Vitals adds another app to check. The recommendations are best treated as prompts to consider recovery alongside how you actually feel.

Battery gains

Apple rates normal battery life at up to 50 hours, compared with 42 hours for the Ultra 3. Around two days between charges is a realistic expectation with mixed everyday use and workouts. Frequent cellular use or prolonged GPS tracking can shorten that interval.

Low Power Mode extends the claimed ceiling to 84 hours. Workout endurance has improved too. Apple quotes up to 18 hours of standard workout tracking and 25 hours in Extended Workout mode.

Max Extended Workout mode raises the claim to 45 hours for outdoor runs, walks and hikes. GPS readings continue every second, but this mode disables alerts and splits. Extended Workout also removes running form metrics. Those compromises matter when planning an event around the longest advertised runtime.

Fast charging is arguably as useful as the larger battery. Apple says 15 minutes can add up to 18 hours of normal use with suitable charging equipment. A short top-up makes it easier to keep the watch on overnight without abandoning daytime tracking.

Outdoor use

Dual-frequency GPS, custom workouts and configurable data views give the Ultra a broad training toolkit. Running metrics include cadence, stride length and ground contact time. Training Load compares recent workout effort with your longer-term activity.

Satellite connectivity adds a route to emergency assistance beyond mobile coverage in supported regions. Emergency SOS and Find My via satellite are included for two years after activation. Find My requires a carrier plan, and reception depends on conditions.

These capabilities explain part of the premium over a standard Apple Watch. They offer more value to regular hikers and endurance athletes than to someone mainly counting steps. The new Steps complication nevertheless makes that everyday task easier, putting the total directly on the watch face.

Audio additions

Sound Recognition can alert you to noises such as alarms, doorbells and a crying baby. It works without your iPhone nearby. Faster Shazam integration also brings music identification into the Smart Stack.

The more ambitious conversation tools remain scheduled for beta release later in 2026. Live Rewind will show a text snippet of the preceding 15 seconds after a double press of the crown. Siri Recap will produce brief conversation summaries.

Both are optional and require a compatible Apple Intelligence-enabled iPhone. Apple says raw audio recordings are not stored. Live Rewind also plays an audible chime when activated. Their usefulness will depend on accuracy and how comfortably they fit into conversations. They should carry little weight in a purchase decision until available.

Summary

The Ultra 4 makes a strong case for iPhone owners who want longer battery life and capable outdoor tracking. Its large display keeps workout data readable at a glance. The Action button provides a useful physical shortcut, while satellite connectivity adds reassurance beyond mobile coverage in supported regions.

The redesigned health sensors and readiness score also give the Ultra more value between workouts. More frequent measurements help users understand recovery and changes throughout the day. Combined with faster charging and around two days of everyday battery life, these improvements make it easier to maintain consistent activity and overnight tracking.