First-generation product — no historical cycle data to predict a successor
Best for: Health-focused users who want passive, 24/7 biometric tracking without a screen on their wrist. Particularly strong for those drawn to WHOOP but put off by the subscription model — the Fitbit Air delivers comparable core health data for $99 outright. Works with both iOS and Android.
Full details →Current model just released
Best for: Trail runners, ultramarathon athletes, and multisport competitors who want full offline maps and long GPS battery without paying Vertix 2S prices. The speaker and depth gauge make the Apex 4 more capable than any previous Apex for mixed adventure and triathlon use.
Full details →| Fitbit Air | COROS Apex | |
|---|---|---|
| Tier | Fitness Tracker | Sports GPS |
| Platform | iOS & Android | iOS & Android |
| Battery | 7 days | 24 days |
| Always-on display | ❌ | ❌ |
| GPS | ❌ | ✅ |
| Cellular | ❌ | ❌ |
| Released | May 7, 2026 | Oct 15, 2025 |
| Cycle length | — | 1126 days |
| Cycle advice | good | good |
| Deals advice | good | neutral |
| Next model | — | — |
Unlike WHOOP, there is no mandatory membership — pay $99 once and use Fitbit Air with the free Google Health app. Google Health Premium ($9.99/month) is optional.
Continuous heart rate, SpO2, HRV, and skin temperature tracking plus background FDA-certified AFib detection, in a 12g pebble designed to be worn and forgotten.
A week between charges, with a 5-minute top-up delivering a full day of use — significantly less downtime than WHOOP's slide-on charging system.
The 46mm Apex 4 delivers 65 hours of GPS tracking and 24 days typical use — enough for multi-day mountain events without charging. The 42mm offers 41h GPS and 15 days.
Global topographic maps with instant rendering, turn-by-turn navigation, POIs, and an underwater depth gauge — the Apex 4 is the first COROS mid-tier with a depth sensor.
Audio alerts, hands-free calling, and voice pin recording — a first for the Apex line, adding practical trail and daily-wear convenience to this mountain sports watch.