Samsung Galaxy Watch Ultra2 (47 mm, LTE) / Amazfit T-Rex 3 (48 mm)

Samsung Galaxy Watch Ultra2 (47 mm, LTE): SM-L715 · 47mm titanium case, LTE; Titanium Silver and Titanium Gray. The US version is SM-L715U and the European/Australian version SM-L715F; LTE bands vary by country.

Amazfit T-Rex 3 (48 mm): 48.5 mm case, 1.5-inch AMOLED; Onyx (black), Lava and Gray colours. The T-Rex 3 Pro, T-Rex 2 and the T-Rex Ultra 2 are separate models.

SpecificationSamsung Galaxy Watch Ultra2 (47 mm, LTE)Amazfit T-Rex 3 (48 mm)
Release year20262024
AvailabilityFrom 7 August 2026 in 106 markets Samsung—
Display1.5-inch (38.5 mm) Super AMOLED; 498 × 498 Samsung1.5-inch AMOLED, 480 × 480 pixels, 322 ppi; Gorilla Glass touchscreen

There is also a night display mode.

Amazfit
BrightnessUp to 5,000 nits

This is peak brightness aimed at readability in sunlight, not sustained full-screen brightness.

Samsung		—
Case47 mm; titanium on the front and back cover areas, plastic and other materials elsewhere in the frame Samsung—
ProcessorSnapdragon Wear Elite; 5 cores (2.1 and 1.95 GHz) Samsung—
Memory and storage2 GB RAM; 64 GB (49.3 GB available) Samsung—
Battery800 mAh typical; up to 60 hours with AOD on, 80 hours with it off

AOD (always-on display) lets you read the watch without raising your wrist but cuts battery life by roughly a quarter.

Samsung		700 mAh; 27 days typical, 13 days heavy use, 40 days battery saver, 81 days clock mode; 42 hours in accuracy GPS mode, 72 hours power-saving GPS, 180 hours maximum GPS mode

A full charge takes about 3 hours; a magnetic charging base is in the box but no USB-C cable. Low-temperature mode gives 28 hours with GPS on and 32 days with it off. The maximum GPS mode works only in hiking and climbing modes.

Amazfit
ChargingFast charging up to about 40% in 30 minutes Samsung—
Operating systemWear OS 7; security updates until 31 July 2031 Samsung—
WirelessBluetooth 6.0; Wi-Fi 802.11a/b/g/n (2.4 and 5 GHz); NFC Samsung—
Cellular4G LTE (FDD/TDD), 3G WCDMA; eSIM

LTE use depends on country and carrier support; the watch can make calls and use data without a phone.

Samsung		—
LocationGPS, GLONASS, BeiDou, Galileo, QZSS; dual-frequency (L1+L5) GPS

Receiving L1 and L5 together reduces errors caused by reflected signals near tall buildings and under trees.

Samsung		—
SensorsOptical heart rate, electrical heart (ECG), BIA, temperature, accelerometer, gyro, barometer, geomagnetic, light

BIA estimates body composition using a weak current through the wrist; ECG readings use the electrical heart sensor.

Samsung		BioTracker 6.0 PPG biometric sensor; accelerometer, gyroscope, magnetometer, barometric altimeter, ambient light, temperature sensor

The watch offers an altitude assistant, storm alerts, compass, sunrise/sunset and tide information, and prompts for blood-oxygen readings at high altitude.

Amazfit
Durability10 ATM; IP69K; EN13319; MIL-STD-810H

Samsung lists 100 m water resistance under ISO 22810 and operation between −20 and 55 °C while worn. EN13319 is a diving equipment standard.

Samsung		—
Buttons and sirenThree buttons and an orange Quick Button; holding it for 5 seconds sounds an 86 dB siren (audible up to 180 m)

Pressing the home button five times starts an emergency SOS.

Samsung		—
Size and weight47.4 × 47.1 × 10.7 mm; 61.5 g Samsung—
Phone compatibilityAndroid 13 or later phone with at least 1.5 GB of memory

Pairing with an iPhone is not supported.

Samsung		—
Case and strap—48.5 × 48.5 × 13.75 mm; stainless-steel bezel, polymer middle frame; 4 buttons; 22 mm liquid-silicone strap for 145–210 mm wrists

The 22 mm strap is a standard width and can be swapped.

Amazfit
Weight—68.3 g (without strap) Amazfit
Water and diving—10 ATM; freediving to 45 metres (147 ft) certified to EN 13319, ISO 6425 and GB/T 18828

10 ATM means withstanding the pressure of 100 metres of still water for up to 10 minutes. Breath-hold training and testing are downloaded through the Zepp app.

Amazfit
Positioning and navigation—Dual-band and single-band modes; 6 satellite systems; offline maps, turn-by-turn directions, route import, back-to-start and off-route alerts

Dual-band positioning receives two frequencies from the satellites to reduce drift from reflected signals among tall buildings and dense trees; it uses more battery. Automatic mode switches settings based on signal strength.

Amazfit
Connectivity—Bluetooth 5.2 (BLE), 2.4 GHz Wi-Fi; microphone; music storage

Wi-Fi is used to download software updates without the phone. The watch shows incoming calls but cannot take Bluetooth calls; quick reply works on Android only.

Amazfit
Sports and health—170+ sports modes (177 listed); recognition of 25 strength and 8 sports movements; 24-hour heart rate, blood oxygen and stress; sleep stages; PAI; Zepp Coach

Chest straps, running/cycling power meters and cycling speed/cadence sensors can be paired; data can be exported to apps such as Strava, komoot and Apple Health.

Amazfit
Compatibility—Android 7.0 and later, iOS 14.0 and later; Zepp app Amazfit