GPS Running Watches / Amazfit T-Rex 3 Pro (48mm) vs COROS APEX 4 (42mm)
Amazfit T-Rex 3 Pro (48mm) vs COROS APEX 4 (42mm)
COROS APEX 4 (42mm)
Free offline topo maps and a titanium bezel for $429 — with a screen you fight in low light.
Wins overall by 0.3 points
Quick Verdict
The COROS APEX 4 (42mm) wins by 0.3 points, which is not enough to settle it. Flagship materials, maps and 38 h of dual-band GPS for $399 — with clumsy map downloads. Pick on the specs that matter to you, not the overall score.
The Amazfit T-Rex 3 Pro (48mm) and COROS APEX 4 (42mm) are both current-generation GPS Running Watch models, and the Amazfit T-Rex 3 Pro (48mm) is $29 cheaper than the COROS APEX 4 (42mm) ($399.99 vs $429). On Display, the Amazfit T-Rex 3 Pro (48mm) leads (9.5 vs 6.2/10) — brightness, resolution and daylight readability, weighing AMOLED sharpness against MIP's always-on-for-free behaviour.. On Build & Comfort, the COROS APEX 4 (42mm) leads (8.6 vs 6.4/10) — case materials, lens (sapphire vs glass), weight on the wrist and durability ratings.. On Battery Honesty, the COROS APEX 4 (42mm) leads (8.8 vs 7.6/10) — how much of the headline battery claim survives the mode you would actually train in: all-systems plus multiband, always-on display, music playing. The number on the box is almost always the slowest, least accurate mode.. Overall, the COROS APEX 4 (42mm) scores 7.9/10 across our 8 scoring categories versus 7.6/10 for the Amazfit T-Rex 3 Pro (48mm), though the gap is close enough that your specific use case should decide it. Below, we break down the full spec sheet, category-by-category scores, and exactly who should buy which one.
Side-by-Side Comparison
| Spec | Amazfit T-Rex 3 Pro (48mm) | COROS APEX 4 (42mm) |
|---|---|---|
| Price | $399.99 | $429.00 |
| Release Year | 2025 | 2025 |
| Display | 1.5-in AMOLED, up to 3,000 nits, sapphire crystal lens, optional always-on | 1.2-in 240x240 3rd-gen transflective MIP, always-on, no AMOLED battery penalty — but DC Rainmaker and Tom's Guide both call it dim indoors and in low light |
| Smartwatch Battery ( days) | 25✓ | 15 |
| Always-On Display Cost | Amazfit's 25-day figure is typical use; heavy use is rated 10 days and one reviewer measured about 18 days alongside 14 h of accurate GPS. Amazfit does not publish a separate always-on display figure. | No always-on penalty — the MIP screen is permanently on. (The 46 mm version is rated 24 days smartwatch and 65 h all-systems GPS if you want the bigger numbers.) |
| Battery, Single-Band GPS ( h) | 85✓ | 41 |
| Battery, Multiband GPS ( h) | 38 | Not published by COROS for the 42 mm in any source reviewed here. For reference the 46 mm is rated 65 h all-systems vs 41 h dual-frequency — expect a similar ~35-40% drop. |
| GNSS Bands | Dual-band (L1+L5) circularly-polarised GNSS. The 85 h headline is the power-saving GPS mode; the accurate dual-band mode is 37-38 h on the 48 mm and about 29 h on the 44 mm. | Dual-frequency L1+L5 chipset covering GPS, GLONASS, Galileo, BeiDou and QZSS. DC Rainmaker warns GPS accuracy degrades noticeably when route navigation is running. |
| Onboard Maps | Free offline contour maps with turn-by-turn, POI search, round-trip routing and auto-rerouting — but you must select and download each map region inside the Zepp phone app and transfer it across. Android Police called the process 'messy and time-consuming' with vague instructions. | Free global offline topographic and landscape maps with street/trail names and POIs, downloaded through the COROS app, plus turn-by-turn on preloaded routes. No ClimbPro equivalent and no automatic rerouting. |
| Music Storage | Onboard storage for sideloaded MP3 files played to Bluetooth headphones. No Spotify and no streaming services. | MP3 files only, sideloaded. No streaming services and no phone-music control. |
| Training Platform & Subscription | The Zepp app and core training/recovery metrics are free. Zepp Aura, the AI sleep and coaching layer, is a paid subscription; the training data itself is not gated behind it. | COROS app and EvoLab analytics are entirely free, no subscription tier. COROS' own metrics, not Firstbeat. |
| External Sensor Support | Bluetooth only — no ANT+. BLE chest straps and Stryd pods pair through Zepp OS. | Bluetooth only — no ANT+ at all, which rules out ANT+-only power meters |
| Data Export | Free sync to Strava, adidas Running, Apple Health and Google Health Connect, plus a TrainingPeaks Zepp OS app; .FIT export via the Zepp app | Free .FIT/GPX export plus auto-sync to Strava, TrainingPeaks, Apple Health and Health Connect |
| Warranty | 12 months | 24 months |
| Colors | Black | Black |
Category Scores
GPS Accuracy
The COROS APEX 4 (42mm) is marginally ahead, 8.0 to 7.8. A gap this small rarely decides a purchase on its own, though it counts if trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world. is your priority.
Battery Honesty
The COROS APEX 4 (42mm) leads clearly here, 8.8 against 7.6 — a 1.2-point margin on how much of the headline battery claim survives the mode you would actually train in: all-systems plus multiband, always-on display, music playing. The number on the box is almost always the slowest, least accurate mode.. If that is what you are buying for, the Amazfit T-Rex 3 Pro (48mm) does not close the gap elsewhere.
Training & Recovery
The COROS APEX 4 (42mm) leads clearly here, 7.8 against 6.8 — a 1.0-point margin on depth of load, readiness and recovery analysis, and how much of it is free rather than gated behind a subscription or an extra chest strap.. If that is what you are buying for, the Amazfit T-Rex 3 Pro (48mm) does not close the gap elsewhere.
Heart Rate
The COROS APEX 4 (42mm) leads clearly here, 7.4 against 6.8 — a 0.6-point margin on optical wrist accuracy during intervals and burst efforts, and whether the watch pairs with ANT+ and/or Bluetooth chest straps as a fix.. If that is what you are buying for, the Amazfit T-Rex 3 Pro (48mm) does not close the gap elsewhere.
Display
The Amazfit T-Rex 3 Pro (48mm) leads clearly here, 9.5 against 6.2 — a 3.3-point margin on brightness, resolution and daylight readability, weighing AMOLED sharpness against MIP's always-on-for-free behaviour.. If that is what you are buying for, the COROS APEX 4 (42mm) does not close the gap elsewhere.
Build & Comfort
The COROS APEX 4 (42mm) leads clearly here, 8.6 against 6.4 — a 2.2-point margin on case materials, lens (sapphire vs glass), weight on the wrist and durability ratings.. If that is what you are buying for, the Amazfit T-Rex 3 Pro (48mm) does not close the gap elsewhere.
Value
The Amazfit T-Rex 3 Pro (48mm) is marginally ahead, 9.0 to 8.6. A gap this small rarely decides a purchase on its own, though it counts if what the watch delivers per dollar against everything else in the comparison at the moment of purchase. is your priority.
Best For
Choose the Amazfit T-Rex 3 Pro (48mm) if…
- • Display matters most to you — the Amazfit T-Rex 3 Pro (48mm) scores 9.5/10 here (brightness, resolution and daylight readability, weighing AMOLED sharpness against MIP's always-on-for-free behaviour.).
- • You want to spend less — it's $29 cheaper.
Choose the COROS APEX 4 (42mm) if…
- • Build & Comfort matters most to you — the COROS APEX 4 (42mm) scores 8.6/10 here (case materials, lens (sapphire vs glass), weight on the wrist and durability ratings.).
- • Battery Honesty matters most to you — the COROS APEX 4 (42mm) scores 8.8/10 here (how much of the headline battery claim survives the mode you would actually train in: all-systems plus multiband, always-on display, music playing. The number on the box is almost always the slowest, least accurate mode.).
- • Training & Recovery matters most to you — the COROS APEX 4 (42mm) scores 7.8/10 here (depth of load, readiness and recovery analysis, and how much of it is free rather than gated behind a subscription or an extra chest strap.).
- • Heart Rate matters most to you — the COROS APEX 4 (42mm) scores 7.4/10 here (optical wrist accuracy during intervals and burst efforts, and whether the watch pairs with ANT+ and/or Bluetooth chest straps as a fix.).
Pros & Cons
Amazfit T-Rex 3 Pro (48mm)
Pros
- +38 h of dual-band GPS and 25 days of typical use for $399.99 — Garmin charges $1,199.99 for 30 h of multiband
- +A 3,000-nit AMOLED behind sapphire with a titanium-alloy bezel at half the price of rivals with those materials
- +Free offline contour maps with genuine auto-rerouting, which even the $749.99 Forerunner 970 does not beat on price
- +10 ATM plus EN13319 freediving certification to 45 m, unusual at any price
Cons
- −Maps must be picked and downloaded region-by-region in the Zepp phone app then transferred — reviewers describe the process as messy and poorly documented
- −The 85 h battery headline is the power-saving GPS mode; the dual-band mode you would actually race on is 38 h
- −No ANT+ and no Spotify or any streaming service — sideloaded MP3 only
- −Zepp's software ecosystem and analytics are a clear step behind Garmin and COROS, and the app is cluttered
- −48 mm and chunky; reviewers found it too bulky for 24-hour wear
COROS APEX 4 (42mm)
Pros
- +Free global offline topo maps with street and trail names at $429 — Garmin charges $749.99 before you get maps
- +Titanium bezel and sapphire glass at a price where rivals use aluminium and Gorilla Glass
- +MIP means the 41 h all-systems figure is what you get, with no always-on display tax
- +Two years of warranty and zero subscriptions anywhere in the platform
Cons
- −COROS does not publish a dual-frequency battery figure for the 42 mm, and dual-frequency is where accuracy actually lives
- −DC Rainmaker measured a real GPS accuracy drop when a route is loaded and navigation is active
- −MIP display is dim indoors and at night compared with every AMOLED rival here
- −No ANT+, no NFC payments and no LED flashlight
- −The depth gauge has no certification and cannot record dives to the app, and there are no dive sport profiles
Shop by Need
FAQs
Is the Amazfit T-Rex 3 Pro (48mm) or COROS APEX 4 (42mm) better overall?+
Based on our 8-category scoring, the COROS APEX 4 (42mm) comes out ahead overall. See the full breakdown in the scores section above — the right pick still depends on which categories matter most for your use case.
Which is better for Display, the Amazfit T-Rex 3 Pro (48mm) or the COROS APEX 4 (42mm)?+
The Amazfit T-Rex 3 Pro (48mm) scores higher on Display (9.5/10 vs 6.2/10) — brightness, resolution and daylight readability, weighing AMOLED sharpness against MIP's always-on-for-free behaviour..
Which is better for Build & Comfort, the Amazfit T-Rex 3 Pro (48mm) or the COROS APEX 4 (42mm)?+
The COROS APEX 4 (42mm) scores higher on Build & Comfort (8.6/10 vs 6.4/10) — case materials, lens (sapphire vs glass), weight on the wrist and durability ratings..
Which is better for Battery Honesty, the Amazfit T-Rex 3 Pro (48mm) or the COROS APEX 4 (42mm)?+
The COROS APEX 4 (42mm) scores higher on Battery Honesty (8.8/10 vs 7.6/10) — how much of the headline battery claim survives the mode you would actually train in: all-systems plus multiband, always-on display, music playing. The number on the box is almost always the slowest, least accurate mode..
Which is better for Training & Recovery, the Amazfit T-Rex 3 Pro (48mm) or the COROS APEX 4 (42mm)?+
The COROS APEX 4 (42mm) scores higher on Training & Recovery (7.8/10 vs 6.8/10) — depth of load, readiness and recovery analysis, and how much of it is free rather than gated behind a subscription or an extra chest strap..
Is the Amazfit T-Rex 3 Pro (48mm) worth the price difference over the COROS APEX 4 (42mm)?+
The Amazfit T-Rex 3 Pro (48mm) is the cheaper option at $399.99 versus $429. Whether the pricier model is "worth it" depends on how much you value its lead in Display.
What's the warranty on the Amazfit T-Rex 3 Pro (48mm) vs the COROS APEX 4 (42mm)?+
The Amazfit T-Rex 3 Pro (48mm) ships with a 12-month warranty; the COROS APEX 4 (42mm) ships with a 24-month warranty. Always confirm current terms on the manufacturer's site before buying.
Should I wait for the next model instead of buying either of these?+
If either model is more than two years old, a successor may be close — check the "Latest Model" link on each product page. Otherwise, both are current, well-supported options and there's no strong reason to wait.
Cheaper Option
Garmin Forerunner 170 (43mm) — $299.99
Premium Option
Suunto Race 2 (stainless steel) — $499.00
Specifications and prices for both products last verified . Scores are calculated from published specifications — see how we compare products.