COROS Apex 4 vs Garmin Forerunner 970: Which GPS Watch Wins?

Overview

The COROS Apex 4 is a rugged, trail-focused endurance watch built around extraordinary battery life and a titanium-and-sapphire build. The Garmin Forerunner 970 is a triathlon-first flagship with an AMOLED display, deep multisport tooling, and 10 ATM water resistance. Both sit at the premium end of the GPS watch market, but they serve different athletes with different priorities.

Specs at a glance

Price: COROS Apex 4 from $429 (42mm) / $479 (46mm); Garmin Forerunner 970 at flagship pricing above $500
GPS battery (dual-frequency, AOD): Apex 4 65h (46mm) / 41h (42mm); Forerunner 970 rated for extended endurance use, confirmed across multi-hour continuous efforts
Display: Apex 4 MIP (always-on, low power); Forerunner 970 AMOLED touchscreen
Water resistance: Apex 4 5 ATM; Forerunner 970 10 ATM
Case: Apex 4 titanium with sapphire glass; Forerunner 970 standard multisport build
Heart rate sensor: Both use wrist optical PPG (light-based blood volume measurement, not electrical)
Multisport profiles: Forerunner 970 covers triathlon, duathlon, and expanded disciplines via firmware; Apex 4 covers trail, cycling, and outdoor multisport
Speaker and microphone: Apex 4 includes both; Forerunner 970 does not

GPS and tracking accuracy

Both watches use dual or multi-frequency GNSS with multi-constellation support, which puts them in the same tier for most land-based activities. The Apex 4 adds COROS Vertical GPS Algorithms paired with an upgraded barometric altimeter, making elevation data more reliable on technical trail and mountaineering routes.

The Forerunner 970 has a documented weakness in open-water swim GPS. In direct testing, it was outperformed by the Apple Watch Ultra 3 in open-water conditions, a meaningful gap for triathletes who rely on swim split accuracy. Signal interruption from arm strokes and water immersion is the physical cause, but the gap was large enough to flag. On land and road, both watches perform at a high level.

Battery life

The Apex 4 wins this category outright. 65 hours of GPS recording with always-on display active and dual-frequency GNSS running is exceptional. The Garmin Fenix E manages around 40 hours in comparable conditions. The Forerunner 970 supports multi-hour continuous GPS recording suitable for long-course racing, but specific published figures from the review are not confirmed beyond real-world ride testing.

For 100-mile ultramarathons, multi-day fastpacking, or alpine objectives, the Apex 4 is the only realistic choice between these two. For a 70.3 or full-distance triathlon, either watch covers the duration comfortably. Garmin's battery manager insights on the Forerunner 970, added in firmware 16.28, help athletes plan race-day power consumption with more precision.

For athletes: who wins?

Trail running and ultramarathon: Apex 4. 65 hours of GPS plus a titanium build and superior altimeter accuracy makes it the clear pick for long mountain efforts.
Triathlon: Forerunner 970, with a caveat. Its expanded multisport profiles, 10 ATM water resistance, and triathlon-specific tooling are better suited here. The open-water GPS weakness is real and worth knowing, but it remains the stronger triathlon platform overall.
Road running and cycling: Tie. Both perform well. The Forerunner 970 offers a better display for data review. The Apex 4 offers longer battery for back-to-back training days without charging.
Recovery and HRV tracking: Tie. Both use wrist optical PPG for HRV measurement. Neither has a meaningful advantage here without a chest strap.

Verdict

The Forerunner 970 is the better watch for triathletes and athletes who train across swim, bike, and run. Its multisport depth, 10 ATM rating, and AMOLED display make it purpose-built for that use case. The Apex 4 is the better watch for trail runners, mountaineers, and anyone whose priority is surviving a long effort without finding a charger. Buy the Forerunner 970 if you race triathlon or want the most polished multisport platform. Buy the Apex 4 if you run ultras, spend days in the mountains, or want maximum battery at a slightly lower price.