Onyx: Fitness & AI Coach
Workout, Recovery, Sleep Score
About
This app acts as a personalized AI fitness coach, analyzing your wearable data to provide tailored advice on training, nutrition, and rest. It offers detailed recovery scores, sleep analysis, and illness early warnings based on your unique metrics.
What's New in Onyx
2.8.1
August 1, 2026
Shared routes now carry your numbers Share a run and the image comes with your distance, time, and pace on it, plus the Onyx mark. No more sending friends an unlabeled squiggle. Log food from your widget The Calories widget gained a Log food button that opens straight to food entry instead of dropping you on the Fuel tab. Bigger text, properly The Today hero and cardio summaries now respond to your text size setting instead of ignoring it. New widgets also read correctly with VoiceOver. Fixes - A Strength or Other workout started on the Apple Watch could save to Health without ever appearing in Onyx. Fixed. - Recovery widgets, complications, and notifications now open the recovery detail directly instead of just the Today tab. - Onyx Pro plans and pricing are clearer, and free trials now show the exact date your trial ends.
MoreSubscription plans
Onyx Pro Yearly
Unlimited AI Coach, smart food log, every Pro feature.
In-App Purchases
$79.99
Onyx Pro Lifetime
Pay once, get forever — every Pro feature we add later.
FAQ
What data does Onyx use to provide coaching?
Onyx reads data from your Apple Watch and other connected wearables via Apple Health, including workout history, sleep patterns, heart rate variability (HRV), resting heart rate, and wrist temperature to offer personalized insights.
How does Onyx score recovery and sleep?
Onyx calculates a recovery score from 0-100 based on HRV, resting heart rate, sleep, and wrist temperature, comparing it to your personal baseline. Sleep is also scored from 0-100, broken down by duration, deep/REM stages, efficiency, and consistency.
Can Onyx help with illness detection?
Yes, Onyx can provide early illness warnings by detecting combined signals like drops in HRV, climbing RHR, and drifting wrist temperature, alerting you before symptoms become apparent.
What are the features of Onyx Pro?
Onyx Pro offers unlimited coaching messages, workout scoring, a smart AI food log, and detailed illness analysis, in addition to the features available in the free version.
What is the pricing for Onyx Pro?
Onyx Pro is available for $4.99 per month, $39.99 per year with a 7-day free trial, or a lifetime purchase of $79.99.
Does Onyx have ads?
No, Onyx does not have advertisements. The app is free to use with core features, with an optional paid upgrade for advanced functionalities.
What devices and platforms does Onyx support?
Onyx requires an iPhone running iOS 18 or later and connects with Apple Health. It is compatible with Apple Watch and most third-party wearables like Whoop, Oura, Garmin, and Fitbit.
How often is Onyx updated?
The latest version of Onyx is 2.3, and it was last updated on May 27, 2026. This indicates a relatively active development cycle.