Amazfit T-Rex 3 (48 mm) / Apple Watch Series 8 (45 mm, GPS)

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.

Apple Watch Series 8 (45 mm, GPS): Apple Watch Series 8, 45 mm aluminium case, GPS model. The 41 mm case, GPS + Cellular and stainless steel versions are separate models; weight and screen size differ.

Specification	Amazfit T-Rex 3 (48 mm)	Apple Watch Series 8 (45 mm, GPS)
Release year	2024	2022
Display	1.5-inch AMOLED, 480 × 480 pixels, 322 ppi; Gorilla Glass touchscreen There is also a night display mode. Amazfit	Always-On Retina LTPO OLED; 396 × 484 pixels; 1143 sq mm display area; up to 1000 nits The LTPO panel can lower its refresh rate a lot, so the screen stays on dimmed when the wrist is down. Apple
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	—
Battery	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	—
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	—
Sensors	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	—
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	Wi-Fi 802.11b/g/n 2.4 and 5 GHz; Bluetooth 5.3 Apple
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	Requires iPhone 8 or later with iOS 16 or later It cannot be used with Android phones. Apple
Chip	—	S8 SiP with 64-bit dual-core processor; W3 wireless chip; U1 (Ultra Wideband) Ultra Wideband is used for close-range location with an iPhone; availability varies by region. Apple
Health sensors	—	Blood oxygen sensor; electrical heart sensor (ECG app); third-generation optical heart sensor The Blood Oxygen app is not for medical use. The ECG app is not intended for people under 22 and may not be available in every country. Apple
Motion and safety	—	High-g accelerometer up to 256 g (Fall Detection and Crash Detection); high dynamic range gyroscope; Emergency SOS; international emergency calling On the GPS model, Emergency SOS needs a nearby iPhone or Wi-Fi Calling; international emergency calling works only on cellular models. Apple
Location	—	L1 GPS, GLONASS, Galileo, QZSS and BeiDou; compass; always-on altimeter This is single-frequency (L1) GPS; drift between tall buildings can be higher than on dual-frequency models. Apple
Storage	—	32 GB Apple
Battery and charging	—	Up to 18 hours; built-in lithium-ion battery; USB-C magnetic fast charging cable Apple’s 18-hour figure is based on 90 time checks, 90 notifications, 45 minutes of app use and a 60-minute workout with music; sleep tracking is not part of that scenario. Apple
Durability	—	Water resistant to 50 metres under ISO 22810:2010; IP6X dust; ceramic and sapphire crystal back Suitable for shallow-water activities in a pool or the sea; not for scuba diving, waterskiing or high-velocity water. Apple
Size and weight	—	45 × 38 × 10.7 mm; aluminium GPS: 38.8 g Apple
Colours	—	Aluminium: Midnight, Starlight, Silver, (PRODUCT)RED Apple