Apple Watch Ultra 4

About Apple Watch Ultra 4

Overview Apple Watch Ultra 4 is the rugged, long-running end of Apple's watch range: a single 49 mm Grade 5 titanium case, built for people who hike, dive, train outdoors or want a watch that survives the weekend without a charger. It carries Apple's full health sensor set, adds a new readiness score, precision dual-frequency GPS, a dive computer rating and satellite messaging. It starts at $799, roughly twice a Series 12, and like every Apple Watch it requires an iPhone. Design and durability One size only: 49 mm tall, 44 mm wide, 12 mm deep, weighing 63.0 g in natural titanium and 63.1 g in black. The case is Grade 5 titanium with a matte finish in two colours, and the display is covered by flat sapphire crystal rather than glass. There is a customisable Action button, and a siren that Apple states can be heard up to 600 feet, or 180 metres, away. The case size is not a specification to skim past — at 49 mm this is a physically large watch, and there is no smaller option in the Ultra line. Display The screen is an Always-On Retina display using wide-angle OLEDs and LTPO3, running 422 × 514 pixels at 326 ppi. It reaches 3,000 nits at peak, which is what makes it readable in direct sun, and drops to 1 nit at minimum for dark conditions without flooding your night vision. Health Sensing System The sensor set covers a second-generation electrical heart sensor, an optical heart sensor, blood oxygen, temperature, a depth gauge, a water temperature sensor, compass, altimeter, accelerometer, gyroscope and ambient light sensor, running on the S11 chip with a four-core Neural Engine and 64 GB of storage. What changed this generation is measurement frequency. Apple states Ultra 4 takes background heart rate readings every five seconds and measures HRV as often as every five minutes — figures it describes as 60 times and 24 times more frequent respectively than Ultra 3. More frequent sampling is the mechanism behind the new readiness score rather than a claim on its own. Readiness and recovery Readiness is the headline addition. Apple states the score is determined each morning by analysing your recent activity, vitals and sleep, and that it adjusts as the day goes on. Training load sits alongside it, showing the effect workouts have on your body over time. Sleep gets its own score, with Apple stating that sleep factors are analysed every night to produce a classification and a number. Training and GPS GPS is precision dual-frequency, covering GPS, Galileo, QZSS and BeiDou. Dual-frequency is the part that matters: receiving two bands is what reduces positional drift in cities and under tree cover, which is why this is a meaningfully better outdoor tracker than a single-band watch rather than just a louder claim. GPS is on the watch, so routes record without a phone. Outdoor and safety features Water resistance is 100 m under ISO 22810:2010, covering swimming, snorkelling, scuba and high-speed water sports, and Apple rates the watch for recreational scuba diving to 40 m with ±1 m accuracy, backed by the depth gauge and water temperature sensor. Note that the Oceanic+ dive computer app requires its own subscription — that is a third-party app charge, not an Apple Watch subscription. Beyond water, the Action button triggers the 600-foot siren, Crash Detection can automatically call emergency services after a severe car crash, and Fall Detection can do the same after a hard fall. Satellite connectivity Emergency SOS, Messages and Find My work over satellite, which is the feature that separates this watch from almost everything else in the category for anyone who goes beyond cellular coverage. Apple states these are included free for two years with the activation of an Apple Watch Ultra 3 or later. What happens after those two years is not stated, which is worth knowing before treating satellite as a permanent part of the purchase. Battery and charging This is the clearest reason to choose Ultra over Series, and the figures differ sharply by mode. Apple quotes up to 50 hours of normal use and up to 84 hours in Low Power Mode. Workout tracking is up to 18 hours, Extended Workout up to 25 hours, and Max Extended Workout up to 45 hours. Charging reaches about 80% in roughly 45 minutes; 15 minutes on the charger buys up to 18 hours of normal use, and 5 minutes covers up to 10 hours of sleep tracking. Read the mode you will actually use. A hiker tracking GPS all day is living on the 18 to 45 hour workout figures, not the 50-hour headline. Apps and intelligence The watch runs Apple's app ecosystem with Siri, and Apple states Siri AI is rolling out in English. Two limits are worth noting: Apple states Siri AI will not initially be available in the EU, and some Audio Intelligence features are listed as coming in beta late 2026 rather than available now. Cellular models support 5G RedCap and LTE with international roaming, which needs a plan from a carrier. iPhone compatibility Apple states Ultra 4 requires iPhone 11 or later, including iPhone SE second generation or later, running iOS 27 or later. There is no Android support of any kind. For anyone carrying an Android phone, this single requirement ends the comparison before any feature is considered. Subscription and ongoing cost The $799 covers the watch and all of its built-in health, fitness and safety features. No Apple subscription is required. Two optional costs sit nearby and should not be confused with one: a cellular plan from your carrier if you buy a cellular model, and the Oceanic+ subscription if you want the full dive computer. Apple Fitness+ is likewise optional. Who it may suit Ultra 4 may suit an iPhone owner who wants an Apple Watch that lasts a long weekend, trains or travels outdoors, and values satellite messaging and a dive rating they may rarely use but would want when needed. It suits people who prefer a large, rugged watch. It does not suit Android users at all, it is poor value for someone who mainly wants Apple's health features — Series 12 has most of them for about half the price — and a 49 mm case is simply too large for some wrists. Important considerations Several health features carry age limits and exclusions. Apple states the ECG app is intended for people 22 years old or older. Hypertension notifications are not intended for people under 22, those previously diagnosed with hypertension, or pregnant people. Sleep apnea notifications are intended to detect signs of moderate to severe sleep apnea in people 18 or older without an existing diagnosis. Cycle Tracking should not be used for birth control or to diagnose a health condition. These are wellness and screening features, not diagnostic tools, and none replaces a clinician. On availability: Siri AI will not initially be available in the EU, some Audio Intelligence features are listed as coming in beta late 2026, and satellite features are free for two years from activation rather than indefinitely. Battery figures are Apple's own and vary by mode and use. Prices and configurations change; confirm current terms on Apple's own site before buying.