Testing out the COROS APEX 4 for the previous couple of weeks has given me flashbacks to sporting the 2022 Garmin Forerunner 955, my favourite operating watch earlier than Garmin and its rivals started shifting away from MIP shows. Loads of health watch followers detest this development, like my 955-wearing brother-in-law. Whereas I will admit I choose AMOLED shows, the APEX 4 is a nice look ahead to the holdouts.
COROS’s final watch, the NOMAD, challenges the Garmin Intuition 3 in a slender class: reasonably priced, rugged mountaineering watches with weeks of battery life. An MIP show felt like the correct match.
The APEX 4 targets path runners and “mountain athletes” who additionally care about battery life and out of doors visibility. However its $429/479 worth offers it stiffer competitors from the Suunto Race 2, Garmin Forerunner 570, and Polar Vantage M3 — all AMOLED watches, and the primary two with 2,000 nits for glorious readability in direct daylight.
Preliminary ideas
I reviewed the COROS APEX 2 and APEX 2 Professional in 2022 once I was nonetheless comparatively new to wearables. The {hardware} impressed me, particularly the epic battery life, however I might inform that the GPS and HR accuracy could possibly be higher, the well being monitoring and software program had loads of gaps, and the MIP shows have been painfully dim.
Unsurprisingly, the APEX 4 is extra reliably correct (as you may see under), the battery life nonetheless blows me away, and the MIP show has significantly better distinction, making it serviceable — although for no matter cause, the NOMAD’s show is extra readable indoors. I believe the APEX 4’s sapphire layer catches extra obscuring mild.
Most significantly, the APEX 4’s new Ambiq Apollo 510 processor powers the speediest, smoothest maps I’ve seen outdoors of Apple and Put on OS watches, the place most health watch rivals like Garmin are laggy. You now get avenue and path names, and the crown makes it seamless to zoom in to a complicated path flip or out to a wider view in a few seconds.
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My solely complaints are with the turn-by-turn navigation for downloaded programs. It largely works with out situation, however I observed twice that once I got here to a loop, the arrow recommended I’m going in the wrong way that I selected once I made the course.
After I deliberately went astray, the APEX 4 caught it and warned me instantly. However the turn-by-turn instructions do not replace primarily based on which route you are going through, so once I missed my proper flip and circled, it nonetheless advised me to show proper. I hope COROS can handle each of my map nitpicks sooner or later.
With its new processor, the APEX 4 is primed for years of upgrades. Over three years, the APEX 2 added HRV and stress information, sleep high quality, and operating kind evaluation, Strava Stay Segments, and security alerts, amongst dozens of latest options. Whereas Garmin watch updates are likely to dry up after 1–2 years, APEX 4 updates ought to final for much longer.
I particularly anticipate its built-in depth gauge sensor to allow scuba diving in some unspecified time in the future, and COROS advised Chase the Summit that it might use the mic & speaker to allow offline voice instructions sooner or later.
COROS APEX 4 GPS accuracy
Not all dual-band GPS watches are created equal. Having examined almost each smartwatch model’s GPS accuracy, I’ve discovered that COROS’s most up-to-date watches come the closest to Garmin for dependability, with the APEX 4 following that sample. Prepare for some boringly straight GPS traces, with solely a few glitches to talk of.
I took three dual-frequency GPS watches — the Garmin Forerunner 970, Google Pixel Watch 4, and APEX 4 — out for a 19-mile run; whereas Google relies upon primarily on L1 and L5 GPS frequencies, Garmin and COROS additionally pull in different GNSS alerts as wanted.
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By the top, Garmin measured 0.01 miles extra and Google 0.01 miles much less; you possibly can learn my Pixel Watch 4 health check if you wish to see its outcomes, however I’ve targeted on the 2 predominant rivals right here. By and enormous, all nineteen miles confirmed the 2 alerts both overlapping or in shut parallel with one another. They tended to ding concurrently or inside seconds at every mile marker.
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I solely have one criticism: The APEX 4’s remaining map confirmed me warping from my present spot to a earlier one, then again, as seen above. It did not have an effect on my distance outcomes, nevertheless it did add about 50m to my remaining altitude totals. I observed an identical glitch mountaineering with the NOMAD in August, including 170m of additional ascent however no additional distance.
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For a second 8-mile run, fortunately, we’re proper again to fantastically, dully correct GPS information from each the APEX 4 and Forerunner 970, their GPS traces overlapping or paralleling each other for nearly all the run. I’ve additionally observed that the APEX 4 tends to do barely higher with tunnels and underpasses, staying straight whereas Garmin’s line waves barely.
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Throughout a 5-mile hike, neither watch was good, every having moments the place they strayed barely from the satellite tv for pc path path. Each ended with the identical 5.44-mile distance, whereas my Suunto Race 2 measured 5.43 miles.
What’s odd is that COROS measured about 100 ft of additional elevation acquire (1,762 ft) in comparison with Garmin (1,660 ft) and Suunto (1,644 ft). I am undecided what to make of two actions with extra ascent totals, so I will hold testing it in my full APEX 4 overview.
COROS APEX 4 HR accuracy
I’ve typically discovered COROS watches’ HR accuracy to be dependable, however not good, particularly for the very best anaerobic information. I do not thoughts as a result of the COROS HRM is reasonably priced and cozy to enhance your information, and most COROS watches are low-cost, however you’d need the pricier APEX 4 to face by itself deserves.
This graph exhibits how the COROS APEX 4 and Garmin Forerunner 970 optical HR sensors evaluate. COROS and Garmin’s HR averages ended 1 bpm aside, however you possibly can see how the 2 watches react to my adjustments in effort equally quick and usually mirror each other; the one distinction is that COROS’s outcomes have been barely larger.
A extra dependable accuracy check got here throughout my 19-mile run, throughout which I wore a Garmin HRM 200 chest strap as a management group. The COROS APEX 4 ended with the identical 161 bpm common and 178 bpm most price.
You’ll be able to definitely see factors within the graph the place the 2 diverge as I climbed into larger coronary heart charges. The APEX 4 trails behind the chest strap to hit larger HRs, then stays excessive whereas the chest strap measures my effort degree lowering.
The picture above, with the Forerunner synced to my chest strap, exhibits the way you won’t instantly see how arduous you are pushing with the APEX 4 at any given second. So should you used the APEX 4 for an anaerobic monitor exercise, I might anticipate the HR common would fall a few bpm brief. That is frequent for wrist-based optical sensors, however hold that in thoughts.
Wrist-based optical sensors also can battle with sustained, decrease HR ranges, however the COROS APEX 4 matched the Garmin HRM 200 chest strap for HR common and most throughout my two-hour hike. It is intently aligned 90% of the time, with the APEX 4 doing very effectively at catching when my HR rose on robust hills. However there have been a number of moments the place my effort dipped however the APEX 4 stayed 5–10 bpm above my HR.
Is the COROS APEX 4 the correct look ahead to you?
COROS reps mentioned throughout our APEX 4 briefing that they “will nonetheless have a break up of AMOLED and MIP watches sooner or later,” however that they “nonetheless discover MIP to be an exceptional answer.” The one present COROS AMOLED is the wonderful COROS PACE Professional, however I do not assume there can be an APEX 4 Professional with AMOLED anytime quickly.
With out wading into the MIP vs. AMOLED debate, the APEX 4 is the correct match for individuals who prioritize out of doors visibility and longer battery life. I might argue the most recent 2,000-nit Garmin watches are completely seen outdoor, however their battery life does endure for the additional brightness, whereas the APEX 4 has that basic longevity, to the purpose that I nonetheless have not charged it since I unboxed it.
The APEX 4 jogs my memory of premium health watches from three years in the past, when there was much less business stress so as to add “smarts” such as you’d discover on an Apple or Galaxy Watch. The UI revolves solely round health: What’s subsequent in your marathon coaching plan, how a lot coaching load, have you ever constructed up, and the way does your HRV, stress, and sleep play into your restoration?
However I am much less tolerant of sure issues in 2025 than I used to be in 2022, like how the essential COROS UI crams dozens of instruments into an annoying, rotating Toolbox, or the overly-large “COROS” label subsequent to the show that detracts from its premium look.
Selecting or skipping the APEX 4 comes right down to your priorities as an athlete. Switching to the Forerunner 570, for instance, would internet you a flashlight, every day run ideas, higher music apps, contactless funds, and (arguably) a greater show, however would lose you sapphire glass, a extra fashionable metal bezel, offline maps, and 5–11 days of battery life.
The APEX 4 is what grumbling Garmin customers say that they need: A return to the MIP days, the place they targeted on health necessities and battery life over costly bells and whistles, with an affordable worth and no irritating feature-locking of one of the best options like maps.
I will have a full overview coming quickly with extra function testing, nevertheless it’s undoubtedly one of many greatest operating watches of 2025…should you do not choose AMOLED.
The COROS APEX 4 gives a 1.3-inch AMOLED contact show with sapphire glass, 41 hours of dual-band GPS with a 24-day battery life general, 32GB of storage for music, maps, and routes, and a mic & speaker for Bluetooth calls and Voice Pin diary entries throughout your hikes, that are then saved to your actions to share with mates. It is constructed for severe out of doors athletes.
