True VO2 Max — Cardio Fitness

True VO2 Max gives you lab-like cardio fitness insights using your Apple Watch — now indoors too.

Stop getting misleading VO₂ max drops from heat, humidity, altitude, smog, or tough outdoor conditions. We correct for real-world factors so you can trust your fitness trend. And with our first-of-its-kind Indoor Treadmill VO₂ Max, you can track cardio fitness even when you run inside.

No account required.
No ads.

▷ INDOOR TREADMILL VO₂ MAX
- Estimate VO₂ max from indoor treadmill runs
- Perfect for winter, rain, or night runs
- See indoor fitness changes clearly — without outdoor weather noise

▷ CORRECTED VO₂, ANY WEATHER
- Removes temperature, humidity, altitude, heat, cold, etc.
- Raw vs Corrected shown side-by-side
- Trust the trend, not the temperature

▷ SCIENCE-BACKED CORRECTIONS
- Research-based penalties for weather & elevation
- Transparent impact per condition
- Spot real changes vs. bad weather

▷ IMPACT RESULTS
- Automatic processing the moment you finish your workout
- Be first to see your real fitness trend — no more confusion
- See progress even when conditions make it look worse

▷ AUTOMATIONS
- Apple Watch sync
- Health app sync
- VO2 corrections, no manual input needed

▷ WHAT'S FREE?
- No ads
- Unlimited runs/workouts
- Corrected VO₂ max vs. weather
- Raw Apple Watch VO₂ max vs. Corrected VO₂ max
- Weather logging
- Record your activities
- Basic insights about your performance 

▷ WHAT'S PLUS?
- Indoor Treadmill Watch app
- Instant weather capture as soon as you finish your workout
- Most accurate VO2 max correction every time
- Clear & transparent impact per weather condition
- Improve your VO₂ max with Full Insights
- Personalized performance takeaways
- And more

Try Plus free for 7 days. Cancel anytime.

▷ PRIVACY
- No account needed
- No tracking
- No ads
- No personal data collected
- No third-party SDKs
- All logged info (runs, corrected VO2 max, etc.) remains on-device

Not a medical device. True VO2 Max is for fitness and wellness only.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/