Amazfit T-Rex 3 (48 mm) / Apple Watch Series 6 (40 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 6 (40 mm, GPS): Apple Watch Series 6, 40 mm aluminium case, GPS (2020). The 44 mm and GPS + Cellular versions, stainless steel/titanium cases and the Nike and Hermès editions are separate.

SpecificationAmazfit T-Rex 3 (48 mm)Apple Watch Series 6 (40 mm, GPS)
Release year20242020
Display1.5-inch AMOLED, 480 × 480 pixels, 322 ppi; Gorilla Glass touchscreen

There is also a night display mode.

Amazfit
Always-On Retina LTPO OLED; 324 × 394 pixels, 759 mm² display area; 1000 nits

The Always-On display keeps the time and complications visible with the wrist down.

Apple
Case and strap48.5 × 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
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Weight68.3 g (without strap) Amazfit—
Water and diving10 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
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Battery700 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
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Positioning and navigationDual-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
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SensorsBioTracker 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
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ConnectivityBluetooth 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
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Sports and health170+ 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
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CompatibilityAndroid 7.0 and later, iOS 14.0 and later; Zepp app AmazfitRequires an iPhone 6s or later with iOS 14 or later Apple
Case and version—40 mm aluminium case, GPS; Silver, Space Gray, Gold, Blue, (PRODUCT)RED

Stainless steel and titanium cases were only sold in the GPS + Cellular version. The 44 mm model uses the same chip but has a different display and weight.

Apple
Water resistance—50 metres (ISO 22810:2010)

Suitable for shallow-water swimming in a pool or the sea, but not scuba diving, waterskiing or high-velocity water.

Apple
Chip—S6 SiP with 64-bit dual-core processor; W3 wireless chip; U1 Ultra Wideband chip

Ultra Wideband availability varies by region.

Apple
Storage—32 GB Apple
Health sensors—Blood oxygen sensor (Blood Oxygen app), electrical heart sensor (ECG app), third-generation optical heart sensor

Apple states Blood Oxygen measurements are not for medical use and are only designed for general fitness and wellness. The ECG app is not intended for people under 22.

Apple
Other sensors and safety—Always-on altimeter, compass, accelerometer up to 32 g with fall detection, gyroscope, ambient light sensor; Emergency SOS

On the GPS model, Emergency SOS needs the iPhone nearby; otherwise the watch must be on a known Wi‑Fi network with Wi‑Fi Calling on. International emergency calling is only on the cellular model.

Apple
Wireless—Wi‑Fi 802.11b/g/n 2.4 and 5 GHz; Bluetooth 5.0

LTE and UMTS are only on GPS + Cellular models.

Apple
Battery and charging—Built-in lithium-ion battery; up to 18 hours; magnetic charging cable (1 m)

The 18-hour figure comes from Apple’s August 2020 testing with pre-production watches paired to an iPhone; it varies with use.

Apple
Other—Speaker, microphone, Apple Pay, GymKit; ceramic and sapphire crystal back Apple
Size and weight—40 × 34 × 10.7 mm; 30.5 g (aluminium, without band) Apple