Heart health app

Your heart health data, decoded.

Your Apple Watch already collects a stream of heart data. Reps turns it into something you can read — resting heart rate trends, a fitness age, and cardio recovery signals — from the watch you already wear.

Download on the App Store

Free to try · No extra hardware

The numbers your watch collects, finally readable

A watch full of heart data is only useful if you can see what it means.

Reps turns Apple Watch resting heart rate, heart rate variability, and cardio fitness into clear trends over time. Instead of a wall of daily numbers, you see the direction: is your resting heart rate drifting down as your training pays off, or creeping up because you're run down?

On top of the trends, Reps gives you a fitness age — a single number built from your VO2 max and heart data that tells you how your cardio fitness stacks up against your years, with insight into what's moving it. It's the kind of read that usually lives buried in a health app, brought forward and made to mean something.

Resting heart rate trends

Watch the line that quietly tracks your fitness and your recovery — down when you're adapting, up when you're overreaching.

Fitness age

A single number from VO2 max and heart data, with what-moves-it insight, so cardio fitness stops being abstract.

HRV as a recovery signal

Follow heart rate variability as its own trend and compare it with your Readiness Score, training, and recovery.

No extra device

Everything comes from the Apple Watch you already own. Nothing to buy, nothing to charge on the side.

Heart data that actually changes your day

Most heart trackers stop at showing you a chart. Reps builds the daily Readiness Score from sleep, resting heart rate, and recent strain, while HRV remains a separate trend you can compare with the rest of your recovery picture. Rex can answer questions like "is my resting heart rate normal for me lately?" from your own history.

Reps is not a medical device. ECG belongs to Apple Watch; Reps focuses on everyday heart trends and does not diagnose conditions. See a clinician for medical concerns.

Related reading

  • Overtraining detectionwhy a resting heart rate creeping up for weeks only means something alongside your HRV and load.
  • HRV normal range by agehow wide healthy ranges really are, and why your own baseline is the only fair comparison.

Common questions

What heart metrics does Reps show?

Reps shows Apple Watch resting heart rate, heart rate variability, and cardio-fitness signals as readable trends plus a fitness-age estimate.

Does Reps take an ECG?

No. ECG belongs to Apple Watch. Reps focuses on everyday heart metrics such as resting heart rate, HRV, and cardio fitness, turning them into trends and recovery context.

What is fitness age?

Fitness age is a single number that summarizes your cardio fitness relative to your years, built from VO2 max and heart data, with insights into what moves it up or down.

Is Reps a medical device?

No. Reps surfaces trends to help you understand your training and recovery. It is not a medical device and does not diagnose heart conditions — see a clinician for medical concerns.

Heart health app

Understand your heart, every day.

Trends, fitness age, and recovery signals from the watch on your wrist. Free to try.

Free to download • Built for iPhone + Apple Watch