Between the T-Rex 3 and Watch Ultra 2, the T-Rex 3 comes out ahead in battery life, while the Watch Ultra 2 wins on peak brightness and display size. Overall, the T-Rex 3 scores 79.7 and the Watch Ultra 2 scores 60.5 on our Mars Score.
Which should you buy?
The T-Rex 3 is the clear pick on raw spec strength, leading by 19.2 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the T-Rex 3 if your top frustration with your current device is running out of charge before the day ends — endurance is the lead spec here. The biggest gaps in its favor are battery life.
Pick the Watch Ultra 2 if the display is what you stare at all day — refresh rate, brightness, or sharpness is where the difference will be most visible. Its strongest claims are peak brightness, display size, weight, among others.
Both ship with comparable spo2, water resistance, so those specs don't separate the two — focus on the differences below.
Bottom line: the T-Rex 3 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Amazfit - T-Rex 3 wins
- ▲Battery life — 1766.67% more. 672 h vs 36 h.
Why Apple - Watch Ultra 2 wins
- ▲Peak brightness — 50.00% more. 3000 nits vs 2000 nits.
- ▲Display size — 28.00% more. 1.92 " vs 1.5 ".
- ▲Weight — 6.60 g less. 61.4 vs 68.
- ▲Has ECG.
- ▲Has Cellular.
Spec comparison
Design
| Spec | Amazfit - T-Rex 3 | Apple - Watch Ultra 2 |
|---|---|---|
| Case size | 48.5 mm | 49 mmlead |
| Weight | 68 g | 61.4 glead |
| Case material | polymer | titanium |
| Water resistanceⓘ | 10 ATM | 10 ATM |
Display
| Spec | Amazfit - T-Rex 3 | Apple - Watch Ultra 2 |
|---|---|---|
| Display size | 1.5 " | 1.92 "lead |
| Always-on display | true | true |
| Peak brightnessⓘ | 2000 nits | 3000 nitslead |
Health & Fitness
| Spec | Amazfit - T-Rex 3 | Apple - Watch Ultra 2 |
|---|---|---|
| ECG | false | truelead |
| SpO2 | true | true |
| Temperature sensor | true | true |
| Sleep tracking | true | true |
| Blood pressure | false | false |
Battery & Connectivity
| Spec | Amazfit - T-Rex 3 | Apple - Watch Ultra 2 |
|---|---|---|
| Battery life | 672 hlead | 36 h |
| GPS | true | true |
| Cellular | false | truelead |
| NFC | false | truelead |
| OS | Zepp OSlead | watchOS |
Frequently asked
Which has longer battery life, T-Rex 3 or Watch Ultra 2?+
T-Rex 3 lasts 672h vs 36h.
Do T-Rex 3 or Watch Ultra 2 support ECG?+
Watch Ultra 2 supports ECG; T-Rex 3 does not.
Which has cellular, T-Rex 3 or Watch Ultra 2?+
Watch Ultra 2 offers a cellular variant; T-Rex 3 is Wi-Fi only.
Spec-level deep dives
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