The Coros Apex 4 represents a significant step forward for Coros's mountain-focused lineup. The predecessor, the Apex Pro 2, was capable but lacked maps, a speaker, a microphone, and an ECG – the Apex 4 now includes all of those features. For athletes who want a premium watch without paying Garmin flagship prices, the Apex 4 fills a gap that Coros has been circling for years.
Running this watch in Coros's All Systems dual-frequency mode, the Apex 4 measured within +/- 0.02 miles on our known 2-mile course, nearly matching the most accurate watches we've tested. Most excitingly, the track shape held up well under tree cover and against rock walls where earlier Coros watches have drifted. The dual-frequency positioning – which tracks signals from two different satellites for improved accuracy – is a welcome upgrade over the previous version's single-band GPS.
Improvements in heart rate accuracy were a pleasant surprise. Over a 42-minute run, the Apex 4 averaged a difference of just 0.5 BPM against our Polar Verity Sense armband. Wrist sensors always take a few minutes to “warm up,” during which they tend to lag by 4 BPM on average. Once we settled into a steady effort after the first 15 minutes, the gap narrowed to an average of 0.1 BPM. For athletes who want reliable HR data without an external monitor, the Apex 4 delivers.
Whether you're planning a route or trying to re-orient yourself to the map mid-run, the Apex 4 is genuinely helpful for navigating. Even though it's not nearly as bright as an AMOLED display, the always-on MIP screen remains sharp in direct sunlight and renders maps faster than any previous Coros we have tested. The Apex 4 now includes fully detailed maps with street and trail names, a new feature for this tier of Coros watches.
Coros's standard EvoLab training suite carries over, including structured workouts, race predictions, effort pace, and the handy lap undo feature. A third action button on the left side immediately opens the map during activities, speeding up the workflow. The biggest downside to the Apex 4 is that there's no app store, nor does it support third-party apps – what you see when you turn this watch on for the first time is largely what you get.
The redesigned Coros App 4.0 is one of the cleanest companion apps we tested, making it easy to adjust data fields, sync with Strava or Apple Health, and review training loads. Health tracking covers heart rate, heart rate variability, sleep stages, stress, and blood oxygen saturation (SpO2), though it lacks the depth of Garmin's Body Battery or Morning Report ecosystem.
The speaker and microphone are a first for Coros – it's nice to now be able to take phone calls directly from the watch and hear voice alerts during activities. Notification handling is functional, but reply options are limited compared to the Garmin and Apple ecosystems. Widget selection also remains limited compared to Garmin, but the interface on the Apex 4 is at least intuitive. There are no features hidden behind a paywall, which is notable as competitors increasingly introduce subscription tiers.
The Apex 4 packs more extras than any previous Coros watch. The ECG sensor is a meaningful addition – it provides a highly accurate snapshot of your heart activity compared to the continuous heart rate sensor. The addition of a speaker and microphone, as well as downloadable music storage, lets you leave your phone behind on runs.
The watch still lacks NFC for contactless payments and has no third-party app marketplace, which keeps it a step behind Garmin's flagship watches. For athletes who prioritize training tools over smartwatch conveniences, the trade-off is reasonable. At least the ECG and music storage, in particular, close two gaps that previously pushed folks toward Garmin or Apple over Coros watches.
The Apex 4 features a 1.2-inch MIP display in both the 42mm and 46mm sizes. Both silicone and nylon strap options are available with a quick-release mechanism. With a 50mm body diameter and 14mm thickness, this watch weighs 2.3 ounces – a mid-weight in the watches we tested that sits comfortably on all but the smallest wrists. The titanium bezel and sapphire glass look sharp enough for daily wear yet tough enough for rock scrambles.
The three-button layout now includes a dedicated action button on the left side. Since the crown acts as a scroll wheel, you still have to lock the screen to prevent accidental inputs while you're on the move, a minor frustration that persists across the Coros line.
We measured 63 hours of battery life in All Systems mode, which aligns closely with Coros's 65-hour claim. The MIP display is the hero here – because it draws so little power compared to AMOLED screens, the Apex 4 is smaller than other watches, yet delivers enough power to use the GPS for multi-day trips.
For weekend warriors planning a two-day mountain run, the Apex 4 has more than enough endurance without packing a charger. Charging from empty to full takes about 101 minutes. Even with the always-on display, we could easily go two weeks between charges despite daily use.
The Apex 4 is built for athletes. It's not a smartwatch: there are no contactless payments, no third-party apps, and the widget ecosystem is thin. If those limitations don't bother you and you want a simple, training-focused watch with real maps, long battery life, and a rugged build, the Apex 4 is one of the strongest mid-range GPS watches we have tested.
The Suunto Race 2 is very similar to the Apex 4, and for a few dollars more, you get a brighter AMOLED display that makes it much easier to examine a map in the middle of the day. If you're willing to sacrifice detailed maps in lieu of breadcrumb-style navigation, the Coros Pace 4 is an ultralight, ultra-affordable alternative to the Apex 4. For a full app ecosystem with maps and payments, the Garmin Forerunner 970 is a step up in both features and cost, though it doesn't have the same battery life as the similarly priced Coros Vertix 2S.
| Awards |  Best Bang for Your Buck |
|---|---|
| Price | $479 List Check REI (on sale!) |
Overall Score  |
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| Star Rating | |
| Bottom Line | A premium training watch with full maps and multi-day battery life at a price well below flagship models |
| Pros | Detailed offline maps, premium titanium and scratch-resistant glass, built-in speaker and mic for phone calls, multi-day GPS battery life, heart rhythm monitoring via ECG sensor |
| Cons | MIP display is not as bright as AMOLED, no contactless payment, scroll wheel requires screen lock to avoid accidental inputs |
| Rating Categories | Coros Apex 4 |
| Accuracy (30%) | |
| Activity Use (20%) | |
| Everyday Use (15%) | |
| Extra Features (15%) | |
| Wearability (10%) | |
| Battery Life (10%) | |
| Specifications | Coros Apex 4 |
| Measured Battery Life with GPS | 63 hours |
| Measured Charging Time | 101 min |
| Music Options | Downloaded control, storage |
| Touchless Payment? | No |
| Sensors Included | Heart rate, barometric altimeter, accelerometer, gyroscope, compass, thermometer, blood oxygen level, electrocardiogram |
| Screen Type | MIP |
| Watch Face Material | Sapphire Glass |
| Bezel Material | Titanium Alloy Grade 5 |
| Battery Life Claims | All Systems: 65 hours - 17 hours with music Dual Frequency: 41 hours - 15 hours with music Daily Use: 24 days |
| Model Tested | Standard |
| Size Tested | 46 mm |
| Measured Body Diameter | 50.0 mm |
| Measured Thickness | 14.0 mm |
| Measured Screen Width | 33.0 mm |
| Measured Weight | 2.3 oz |
| Navigation | Detailed, back to start |
| Sleep Tracking | Yes |
| Water Resistance (Max Depth) | 50 m |
| Main Software App | Coros App |
| Compatible with Other Software Ecosystems | Yes |
| Battery Type | Rechargable lithium ion |
| Case Material | Fiber reinforced polymer |
| Strap Material | Silicon or nylon |
| Tools Required to Change Band | No |
| Warranty Offered | 2 year |
