Amazfit T-Rex Ultra vs Samsung Galaxy Watch 4
The Verdict
Amazfit T-Rex Ultra excels as a rugged, battery-focused smartwatch with impressive 20-day endurance and premium AMOLED display (454x454), making it ideal for outdoor adventurers and those prioritizing longevity between charges. Samsung Galaxy Watch 4 counters with superior health features (ECG capability), faster Exynos W920 processor, broader connectivity (NFC, WiFi, optional LTE), and Wear OS 3.0's expansive app ecosystem,though its ~20-hour battery demands daily charging. T-Rex Ultra's 10 ATM water resistance plus fiber-reinforced polymer construction targets extreme sports; Galaxy Watch 4's lighter build (25.9-30.3g vs 89g) suits everyday wearers. At $450 versus $249, the T-Rex Ultra justifies premium pricing for outdoor enthusiasts needing durability and weeks between charges. Galaxy Watch 4 offers better value for mainstream users wanting advanced health monitoring and smart features. Choose T-Rex Ultra for adventure; select Galaxy Watch 4 for daily versatility.
Who Should Buy
Buy the Amazfit T-Rex Ultra if…
- →Excellent 20-day battery life with always-on display
- →Dual-band six-satellite GPS for high accuracy
- →Rugged design with 15 military-grade certifications
Buy the Samsung Galaxy Watch 4 if…
- →First Samsung watch with Wear OS and Google apps integration
- →BIA sensor for body composition measurement (body fat, muscle mass)
- →Lightweight and slim design comfortable for all-day wear
Category Scores
Pros & Cons
Amazfit T-Rex Ultra
Pros
- Excellent 20-day battery life with always-on display
- Dual-band six-satellite GPS for high accuracy
- Rugged design with 15 military-grade certifications
- Free-diving rated to 45 meters
- Offline maps with route import support
Cons
- No ECG, skin temperature, or NFC payments
- No Wi-Fi or cellular connectivity
- Zepp OS app ecosystem is limited
- Heavier than most smartwatches at 89g
- No third-party app store
Samsung Galaxy Watch 4
Pros
- First Samsung watch with Wear OS and Google apps integration
- BIA sensor for body composition measurement (body fat, muscle mass)
- Lightweight and slim design comfortable for all-day wear
- ECG and blood pressure monitoring (Samsung phones only)
- Affordable entry into Samsung's smartwatch ecosystem
Cons
- Battery life of 20 hours typical requires daily charging
- Gorilla Glass DX+ scratches more easily than sapphire crystal
- Many health features locked to Samsung Galaxy phones
- Wear OS 3 was buggy at launch with limited app support
Full Specifications
| Spec | Amazfit T-Rex Ultra | Samsung Galaxy Watch 4 |
|---|---|---|
| Software | Zepp OS 2.0 | Wear OS 3.0 (One UI Watch 4) |
| Body | ||
| Weight | 89 g | 25.9 g (40mm) / 30.3 g (44mm) |
| Case material | Stainless steel bezel, fiber-reinforced polymer case | Aluminum with Corning Gorilla Glass DX+ |
| Water resistance | 10 ATM, ISO 22810 certified for free-diving to 45m | 5ATM + IP68, MIL-STD-810G |
| Health & Sensors | ||
| ECG | ||
| SpO₂ | ||
| Skin temperature | ||
| Heart rate | ||
| Sleep tracking | ||
| Battery | ||
| Battery life | Up to 20 days typical use, 80 hours GPS | Up to 40 hrs (typical ~20 hrs) |
| Display | ||
| Size | 1.39 inch | 40mm / 44mm |
| Type | AMOLED | Super AMOLED |
| Always-on display | ||
| Resolution | 454 x 454 | 396 x 396 / 450 x 450 |
| Connectivity | ||
| GPS | ||
| NFC | ||
| Wi-Fi | ||
| Cellular | ||
| Bluetooth | 5.0 | 5.0 |
| Processor | ||
| Chipset | — | Exynos W920 |
Related Comparisons
This comparison is based on verified manufacturer specifications covering display, performance, camera, battery, and build quality. Scores are generated by analyzing specs across weighted categories on a 10-point scale. Learn more about our methodology.
Explore more in smartwatches, see all Amazfit products or all Samsung products. View full details for the Amazfit T-Rex Ultra or the Samsung Galaxy Watch 4.