Comparison

VO2 Max Tracker vs AXON Readiness

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

VO2 Max Tracker

Measure your cardio fitness (VO₂ max) using a treadmill test and track your progress. Create or select from pre-made HIIT workouts, with real-time guidance on target zones. Integrates with Apple Watch and Bluetooth heart rate monitors.

Highlights
  • VO₂ max testing on treadmills
  • HIIT workout creation and selection
  • Real-time target zone guidance
  • Apple Watch and heart rate monitor integration
  • Workout history with heart rate graphs
  • iCloud data synchronization
Features
Read full description

Use Zephyrus to test your cardio fitness (VO₂ max) on a treadmill, and track your improvement. You can also use Zephyrus to do HIIT workouts. The app comes with a selection of workouts, and lets you create your own workouts. Zephyrus tells you when the target zone changes. To get your heart rate in the app, you can use Apple Watch or heart rate monitors with Bluetooth. Garmin watches with Virtual Run are supported. Cardio fitness is measured with a modified Bruce protocol test you can perform on most treadmills. The test consists of stages with increasing intensity and ends when you reach 85% of maximum heart rate. You can do HIIT workouts on Apple Watch, so you don't have to bring your phone. Your past workouts are saved to your workout history, where you can see the heart rate graph and calories burned. Your data is stored in iCloud, which makes it accessible across your Apple devices. Always consult with a healthcare provider before starting any new exercise program. Exercise can carry risks, especially for people who have certain medical conditions or who have not been physically active in a long time. It's important to understand that using this app does not replace a doctor's advice or treatment. If you would like to report an issue or request a feature for the app, feel free to contact the App Support email. Terms of use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

AXON Readiness

Features
Read full description

AXON Readiness is the athlete portal for the AXON Performance platform. Complete your daily readiness check-in, log your training, and give your coach the data needed to guide you at your best. HOW IT WORKS Every morning you fill in a short questionnaire: how did you sleep, how do you feel, how is your energy? The app asks questions one by one. You are done in under a minute. Your coach sees your score directly in their dashboard and can step in when you show a red flag. After your training session, you log your RPE (rate of perceived exertion) and duration. This gives your coach a complete picture of your training load over time. FEATURES - Daily readiness check-in - RPE Training Log after each session - Personal score history (28 days) - Daily reminder at a time of your choice - Directly connected to the coach dashboard WHO IS IT FOR AXON Readiness is for athletes coached through the Axon Performance platform. You need an invitation from your coach to log in. Coaches and clubs interested in using the platform can get in touch via axonperformance.io.

Screenshots

VO2 Max Tracker4 screens
AXON Readiness4 screens

Verdict

The call

The clearest difference is in-app purchases: AXON Readiness at none against VO2 Max Tracker's 6. AXON Readiness also leads on update cadence (every 6 days vs every 2 weeks). VO2 Max Tracker's advantage is device support (3 vs 1). On price, ads and iOS requirement there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. VO2 Max Tracker sells 6 in-app purchases, starting at $4.99 per 7 days. AXON Readiness asks for nothing beyond the download.

UpkeepUpdate frequency

VO2 Max Tracker ships an update every 2 weeks, AXON Readiness every 6 days. The most recent releases landed on October 30, 2026 and October 28, 2026 respectively.

Scorecard3 real differences · 6 level
VO2 Max Tracker versus AXON Readiness: the parameters behind the verdict, then further details
ParameterVO2 Max TrackerAXON Readiness
PriceFreeFree
Rating4.0 (1 ratings) — better—
Number of ratings1 — better—
Update frequencyEvery 2 weeksEvery 6 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreemium—
DevicesiPhone, iPad, Apple Watch — betteriPhone
Requires iOS18.617.0 — better
Further details — not scored
Size17 MB3 MB
Age rating4+4+
DeveloperHavard TrymanMohammed Amine Allai

In-app purchases

6 purchases

VO2 Max Tracker

Subscriptions6
  • Pro (Weekly)7 Days trial$4.997 Days
  • Pro (Monthly)3 Days trial$7.991 Month
  • Pro3 Days trial$8.997 Days
Show 3 more
  • Pro$24.991 Year
  • Pro (Yearly)3 Days trial$24.991 Year
  • Pro (Yearly)$59.991 Year
None

AXON Readiness

No in-app purchases

Questions

Is VO2 Max Tracker free?
VO2 Max Tracker is free to download, with in-app purchases available.
Is AXON Readiness free?
AXON Readiness is free to download, with no in-app purchases.
Do VO2 Max Tracker or AXON Readiness have ads?
Neither VO2 Max Tracker nor AXON Readiness shows ads.
Which is updated more often, VO2 Max Tracker or AXON Readiness?
VO2 Max Tracker ships an update every 2 weeks, and AXON Readiness every 6 days. Most recently, VO2 Max Tracker was updated on October 30, 2026 and AXON Readiness on October 28, 2026.

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