Apple Watch Ultra 4 vs Samsung Galaxy Watch Ultra2

Samsung announced Galaxy Watch Ultra2 at Unpacked on 22 July 2026 and put it on general sale on 7 August 2026. Apple’s Ultra 4 followed, announced on 9 September 2026 and in stores from 18 September 2026. Both carry the Ultra name and a titanium case, but they run different systems: watchOS 27 on Ultra 4, Wear OS 7 with One UI 9 Watch on Ultra2.

The specs side by side

Spec	Apple Watch Ultra 4	Samsung Galaxy Watch Ultra2
Announced	9 September 2026	22 July 2026
Works with	iPhone 11 or later, iOS 27	Android 13 or newer with Google Mobile Services
Software	watchOS 27	Wear OS 7, One UI 9 Watch
Case	49 × 44 × 12mm titanium	47.4 × 47.1 × 10.7mm titanium
Weight	63.0 g natural; 63.1 g black	61.5 g
Display	LTPO3 OLED, 422 × 514, up to 3,000 nits	1.52-inch Super AMOLED, 498 × 498, up to 5,000 nits
Chip and memory	S11; 64GB	Snapdragon Wear Elite; 2GB + 64GB
Battery	Up to 50 hours normal use	800 mAh; up to 60 hours with always-on
Fast charge	About 80% in 45 minutes	About 40% in 30 minutes; 100% in about 90
GPS	Precision dual-frequency	L1+L5 dual-frequency
Water	100m; EN 13319 to 40m	10 ATM; IP69K; EN13319
Satellite	SOS, Messages, Find My	None listed
US price	$799	$699.99

Your phone settles it

Ultra 4 needs an iPhone 11 or later on iOS 27, pays with Apple Pay through participating card issuers, and supports GymKit. Ultra2 needs an Android phone on Android 13 or newer with more than 1.5GB of RAM and Google Mobile Services, and it pays through Samsung Wallet over NFC where your card issuer supports it. Neither crosses over, and the $100 between their US list prices won’t change that.

Screens and cases

Ultra 4’s Always-On LTPO3 screen is 422 by 514 pixels at 326 pixels per inch, with 1,245 square millimeters of active area under flat sapphire. It peaks at 3,000 nits, dims to 1 nit, and refreshes the always-on face once a second (1Hz).

Ultra2 is a 47mm watch with a 1.52-inch, 38.5-millimeter Super AMOLED at 498 by 498 pixels, under sapphire, with a full-color always-on display. Samsung claims up to 5,000 nits and calls that a first for a smartwatch, based on a June 2026 market survey. The fine print matters: that’s a localized peak under bright ambient light, and full-screen brightness may differ. Ultra 4’s 3,000 nits is the same kind of peak claim, so don’t read 5,000 nits as five times as bright as a 1,000-nit watch in every scene.

The cases are close. Ultra 4 is 49 by 44 by 12 millimeters and weighs 63.0 grams in natural titanium or 63.1 in black. Ultra2 is 47.4 by 47.1 by 10.7 millimeters and 61.5 grams, and Samsung says it’s 12 percent thinner than the previous Galaxy Watch Ultra despite the bigger battery. It comes in Titanium Silver and Titanium Gray, with colors varying by market, and uses Samsung’s Marine, PeakForm and Trail bands rather than Apple’s Ultra band fitting, so straps don’t swap between the two.

Battery and charging

Battery	Apple Watch Ultra 4	Samsung Galaxy Watch Ultra2
Capacity	Not published	800 mAh
Everyday	Up to 50 hours normal use	Up to 60 hours with always-on display
Low power	Up to 84 hours Low Power Mode	Not published
GPS	18 hours outdoor workout; 25 Extended; 45 Max Extended Workout	Up to 20 hours GPS tracking; 16 hours following a GPX route
Charging	About 80% in 45 minutes	About 40% in 30 minutes; full in about 90 minutes

Samsung calls the 800 mAh cell the biggest in any Galaxy Watch, with 35 percent more capacity than the previous Ultra, and Ultra2 is the first Galaxy Watch with what Samsung calls Fast Charging. Its GPS figures come with Samsung’s caveats about weather, buildings and trees. Apple’s longest GPS figure, 45 hours, is for Max Extended Workout on outdoor runs, walks and hikes, with GPS checking your position every second. Ultra 4 charges on a magnetic fast charger to USB-C.

The two companies test differently, so 60 hours with the screen always on and 50 hours of Apple’s normal use aren’t a straight race. Either way you’re charging every two days or so. If you want a watch that runs for weeks, neither is it; that’s Garmin’s territory.

Satellite and safety

Ultra 4 sends Emergency SOS, Messages and Find My over satellite; Samsung doesn’t list any satellite feature for Ultra2. Ultra 4’s Action Button can sound a siren Apple says can be heard about 180 meters away, or start a workout or the flashlight. Ultra2 has fall detection and a siren too, with Samsung’s notes that loudness varies and that reaching emergency contacts needs a network connection.

Trail, dive and GPS

Both use dual-frequency GPS. Ultra 4’s precision dual-frequency system uses GPS, Galileo, QZSS and BeiDou, and Apple calls it the most accurate on-device GPS in a sports watch; Ultra2 uses L1 and L5, which Samsung calls highly accurate GPS tracking. Both are the companies’ own claims.

Ultra2’s outdoor extras live in Samsung Health. Trail Run, an Ultra2-only mode, tracks elevation, climbing progress and terrain impact, and its Nutrition Alert gives hydration guidance based on sweat loss. You can import GPX routes for turn-by-turn hiking and cycling with Climb Guidance, connect cycling cadence, power and speed sensors straight to the watch without the phone in the middle, and follow Running Coach, a three-to-five-week program. Some heart-rate features ask for a 10-minute outdoor GPS setup first.

Ultra 4’s outdoor tools are Apple’s workout set: running power and Race Route, hiking with Backtrack, U.S. topographic maps and curated hikes in all 63 U.S. national parks, cycling Functional Threshold Power, and SWOLF for swimming.

The dive ratings meet at 40 meters under EN13319. Ultra 4 is water resistant to 100 meters under ISO 22810, its depth gauge is accurate to about 1 meter, it reads water temperature, and dive apps such as Oceanic+ open automatically at 1 meter. Ultra2 is rated 10 ATM, which Samsung equates to 100 meters under ISO 22810, with IPX8 and IPX9K water-jet protection and an IP69K rating; with auto-launch on, it tracks dive depth, time and water temperature. Samsung says a Mares Ultra2 Diving app with ascent and descent speed and safe-dive limits is coming later, as a Wear OS exclusive for two years, so don’t assume it’s on the watch when you buy it.

For durability, Ultra 4 has IP6X dust protection and a list of specific MIL-STD-810H tests. Samsung lists IP69K and MIL-STD-810H certification covering temperature, altitude, humidity, salt fog, dust, vibration and drop, among other tests. Samsung’s lab range for on-wrist use, minus 20 to 55 degrees Celsius, matches Apple’s for Ultra 4, and Samsung notes that charging and some functions can be limited at the extremes.

Health

Ultra 4’s Health Sensing System pairs optical and electrical heart sensors. Apple says it checks your heart rate in the background every five seconds, and you get a daily readiness score from 0 to 10. Sleep tracking covers stages and a Sleep score, with sleep apnea notifications where available, and ECG, Blood Oxygen and hypertension notifications depend on your region.

Ultra2 uses Samsung’s BioActive sensor, which combines an optical bio-signal sensor, an electrical heart signal sensor and bioelectrical impedance, and it leans on scores:

• Energy Score: Samsung’s daily readiness-style number.
• Heart Health Score: a lifestyle score from sleep time, BMI, vigorous activity and, in the US, blood-pressure trend. It needs about 24 hours of wear.
• Blood-pressure estimate: a morning reading that needs calibrating against a cuff and doesn’t replace one.
• Daily Cardio Load: needs a week of records, with 28 days recommended, on Watch7 or later with One UI 9 Watch.
• Fitness Index: built from bioelectrical impedance, VO2 max and your activity history.
• Sleep Coaching: sorts you into one of eight sleep-animal types after a week, alongside FDA-cleared sleep apnea risk detection for moderate to severe apnea in select countries.

Samsung’s Ultra2 specs include the electrical heart sensor but don’t restate an ECG app. None of these scores, on either watch, is a diagnosis; ask a doctor what they mean for you.

Chips and connectivity

Ultra2 runs Qualcomm’s Snapdragon Wear Elite (SDW6100), a 3-nanometer penta-core chip, with 2GB of RAM and 64GB of storage. It has Bluetooth 6.0, Wi-Fi on 2.4GHz and 5GHz, and LTE, which in the US comes with carrier limits.

Ultra 4 runs watchOS 27 on S11 with 64GB of storage. It has Wi-Fi 4, Bluetooth 5.3 and a second-generation ultra-wideband chip, and the cellular model, A3579, supports 5G RedCap and LTE.

Price

Samsung sells Ultra2 for $699.99 at samsung.com in the US; that’s the list price, not a UK price or a figure after trade-in credit. Ultra 4 starts at $799 in the US. Promotions that bundle store credit come and go, so check both stores before you buy.