Measure your
VO2 max.
Then raise it.
Five fitness tests. HIIT and Zone 2 training. A personal plan and a world leaderboard.
One app, on your phone and your wrist.
A number is a start.
Here's what comes next.
Find your baseline. Build your fitness. See the work paying off.
Five tests.
Your starting line.
Beep, Yo-Yo, Cooper, Balke and 2.4 km / 1.5 miles. Follow the cues and estimate your VO2 max from your performance.
Which test should I take? ↗Give hard days
a structure.
Nordic 4x4, Tabata or your own intervals.
rhythm.
Zone 2.
Tuned to your heart.
Build your aerobic base. Your Watch cues you when you drift out of range.
Meet your easier days ↗
Leave your phone
in the bag.
Tests, workouts, audio and haptics. All on your wrist.
Made for Apple Watch ↗Beyond
one number.
Heart rate zones, effort and your training history.
Look closer ↗
Find your place.
A world leaderboard with checks on eligible scores.
Field tests estimate VO2 max; they do not directly measure oxygen consumption as a laboratory test does.
And more.
The little details that make the bigger picture.
A plan for your next 12 weeks.
Structured sessions based on your starting fitness, with your next workout ready to follow.
Daily readiness.
HRV, sleep and recent training load come together to help put your day in perspective.
Fitness age.
See your cardiovascular fitness in a different light, alongside your VO2 max trend.
Race predictions.
Explore estimated race times from 5K to marathon, based on your current fitness.
Norms by age and sex.
Put a test result in context and follow how your own performance changes. See the tables ↗
Apple Health, connected.
Bring supported health data and workouts into your training history.
What people are saying.
From the people putting in the work.
“I've been using this app for 2 years, including as a beta tester, and the progress has been huge.”
“Most complete app regarding Vo2 max training. Very nice Apple Watch app too.”
A little more understanding.
Practical guides for your tests, training and the numbers you see.
What Your VO2 Max Score Actually Means
Got a VO2 max number from a lab, field test, or watch? Here is what your score translates to on the FRIEND chart, and what to actually do with it.
Read the guide ↗
How to Run a Beep Test (Step-by-Step Guide)
The 20-meter shuttle test setup, warm-up, pacing strategy, and stop criteria. Everything you need to run a clean beep test from your first attempt.
Read the guide ↗
How to Improve Your VO2 Max: 12-Week Plan
The 12-week training plan that lifted my VO2 max by 6 mL/kg/min: zone-2 base, threshold blocks, HIIT, and the supporting work that actually moves the number.
Read the guide ↗A few things to know.
Do I need an Apple Watch?
The app is available on iPhone and Apple Watch. Watch adds wrist-based heart rate and cues. Check the requirements for your chosen test or workout in the app.
Does a field test measure my VO2 max directly?
Field tests estimate VO2 max from performance. They do not replace a direct laboratory assessment of oxygen consumption.
Can I create my own workouts?
Yes. Create your own interval blocks or use a built-in preset.
Where can I see current prices?
The app is free to download with in-app purchases. Apple shows current regional pricing and eligible offers before you confirm a purchase.
Find out where you stand.
Then take the next step.
Your next chapter starts with a baseline.
Download on the App Store ↗