HRV4Training 4+

A.S.M.A. B.V.

    • $9.99

iPhone Screenshots


The first scientifically validated Heart Rate Variability (HRV) app. HRV4Training provides HRV based insights to help you quantify stress,
better balance training and lifestyle, and improve performance. HRV4Training does not require a heart rate monitor, since it can accurately assess your HRV using the phone's camera.

HRV4Training also works with Apple Watch, the Oura ring and all compatible Bluetooth SMART sensors.

HRV4Training is also the first app that goes beyond simple measurements and provides insights on:
1) acute or day to day HRV changes in response to different stressors (alcohol, travel, sick days, training, menstruation, etc.)
2) long term multi-parameter trends to look at the big picture
3) correlations between physiological measurements and annotations
4) training load analysis, fitness, fatigue, readiness to perform and injury risk
5) VO2max estimation for runners linking the app to Strava or TrainingPeaks and using a heart rate monitor during their workouts
6) Training Polarization analysis (or 80/20)
7) Lactate Threshold Estimation for runners linking the app to Strava or TrainingPeaks and using a heart rate monitor during their workouts
8) Weekly and monthly summaries to track progress.

All data is processed inside the app in order to provide you with actionable interpretations that can help optimizing your training plan and performance.

Supported devices for the camera measurement: iPhones 5, 5S, 6, 6S, 6+, 6S+, SE, 7, 7+, 8, 8+, X, XS, XS Max, XR, 11, 11 Pro, 11 Pro Max, 12 mini, 12, 12 Pro, 12 Pro Max, 13 mini, 13, 13 Pro, 13 Pro Max, 14, 14 Plus, 14 Max, 14 Pro

Currently unsupported devices for the camera measurement: iPhones 4S, iPads and iPods - These devices require a chest strap.

Other features:
- HRV-based advice helps you to adapt your trainings based on objective measures of recovery
- TAGS: lets you tag your sleep, mental energy, muscle fatigue, stress and all other parameters that can help you understand what is influencing your physical condition and physiological stress
- Works with Bluetooth SMART heart rate monitors (a Polar H7 is recommended) or simply your phone's Camera
- Integrates with the Health app (writes heart rate, and sleep, read sleep time)
- Configurable test (single or orthostatic, choose test duration between 1, 3 or 5 minutes)
- Extracts and stores the following features while lying down and/or standing: heart rate, mean of beat-to-beat intervals (AVNN), standard deviation of beat-to-beat intervals (SDNN), square root of the mean squared difference of successive R-Rs (rMSSD), number of pairs of successive R-Rs that differ by more than 50 ms (pNN50), low frequency power (LF, 0.04-0.15 Hz), high frequency power (HF, 0.15-0.40 Hz)
- Shows the PPG signal view to ensure signal quality during the test if the camera is used instead of a bluetooth SMART sensor
- HRV4T Recovery Points to provide a single, straightforward metric to analyze your physical condition
- Population summaries and people like you comparisons to put your data into perspective
- Analysis of compliance and consistency
- Data export via email or Dropbox
- Integrates with TrainingPeaks, SportTracks, Genetrainer and Strava

HRV4Training requires to register an account with your email address, so that your data can be backed up safely and retrieved in case anything happens (app issue, changing phone, etc.).

What’s New

Version 8.2.6

* Pro users can now migrate to the new HRV4Training Pro. Please see how, here:


If you like the updates, please take a few minutes to the review the app. It makes a difference. Thanks!

For any issues, or quick questions contact: or use @altini_marco on Twitter

p.s. let us know if you'd like to experiment more. Happy to send you Camera HRV for free.

Marco & Ale

Ratings and Reviews

3.8 out of 5
218 Ratings

218 Ratings

ssalbo ,

Cool idea, excellent metrics, terrible execution

The ability to measure with a Bluetooth HR strap has degraded significantly. Seriously, Healthnis recording my HR at 54bpm right now, and HRV4TRAINING is showing 154, 99,167, 44, 138, etc. at the end of the measurement “signal quality not optimal, please try again later”.
It all worked flawlessly until the developer started pushing their “pro” website. Now it is almost impossible to get an “optimal reading”. Given the significant investment in time you have to put in to get information out, the readings should not be impossibly finicky. I’ve compared performance to an Apple Watch, a Garmin Fenix, and Elite HRV app. None are as finicky in getting a good reading as HRV4TRAINING has become.

Beekaytab ,

The best app out there for HRV!

What can I say I’m impressed. I’ve tested and downloaded several other HRV apps but they either required an external or didn’t support the new Apple Watch feature that supports HRV. Even though this app doesn’t support the Apple Watch either, it still offered the ability to use my existing iPhone. Don’t be fooled, the iPhone camera works just as great. I used to use the camera for other things to measure HR and I found it to be just as accurate. The HRV was spot on at least referencing against the Apple Watch readings.

As for the app, there are some bugs that I’ve worked with Marco to resolve so while minor he has worked with me. I do acknowledge that most of these HRV apps tend to favor runners, cyclists, or triathletes. Fitness and CrossFit folks are just as interested in peak training. Remember us too!

Lastly, the insights are great and this is the kind of easy advice I was looking for. Integration with other apps to include Strava and Training Peaks is a plus. A negative is the inability to get into the weeds with your data or edit but I just found out they have a Coach app that will allow you to do that and I might have to investigate that!

Overall very impressed and hope they keep developing this app.

SydneyBristowSuperSpy ,

Disappointing $10

They sensor on the Apple watch has been proven to be accurate. (Yet no watch integration) A cardiologist actually laughed at the fact that this app uses a camera. We measured simple heart rate and found this app to be extremely off base. If it uses heart rate as a measurement in the hrv calculations, but it can’t accurately measure that, then how can they claim any accuracy at all?

I appreciate the response. Maybe it would be helpful to inform users before they buy the app that to get a true measurement, you need to have a Bluetooth monitor. Also I will add that I did not say anything about the health app measuring hrv. I just said that when i discusses it with my cardiologist, the cardiologist and I checked the heart rate before and after a stress test on my watch and then tried the hrv app with the camera. HRV4Training was very inaccurate. (If I can’t get an accurate bpm from your app (it was generally at least 20 bpm or more off while measuring with optimal connection) then how can it be trusted to measure R-R intervals?

Developer Response ,

hi there, thank you for your message and sorry to hear about the trouble you have experienced with the app. I would like to point out that it is not true that the Apple watch is an accurate sensor for HRV analysis, and even when it behaves correctly (for example for average heart rate under certain circumstances), it cannot be used for HRV analysis. It is important to understand that the Apple watch cannot be used as a regular sensor (like a chest strap via Bluetooth), as it does not comply to standard protocols, and beat to beat data cannot be transmitted or read (same for raw data). Apple recently added SDNN as an HRV feature that is written to Health from time to time, this feature is not representative of parasympathetic activity, or in other words of physiological stress, and is not very useful unfortunately in the context of short (1-5 minutes) physiological measurements. Additionally, the HRV value is written completely out of context (at random times of the day), hence what is measured is simply the effect of acute stressors or external transitory stressors, which are not really what we are interested in. When using HRV4Training, we try to capture baseline chronic stress, with a measurement clearly contextualized as taken first thing in the morning, before we are affected by other acute or external stressors. Please note also that while there is absolutely no validation of the Apple watch as a device able to measure beat to beat heart rate (RR intervals) and HRV correctly (and even on heart rate literature is conflicting), we did validate our technology, and your cardiologist might be simply misinformed or not up to date on the latest technological developments. This is normal, as this is a new mean to use this technology, but I would maybe ask or read a little more before taking that comment as an absolute truth (or simply ask us!). PPG from cameras has been used for decades, and right now is simply easier to do given the improvements in mobile phone technology. You can check this publication for more details: - Finally, should you have an interest in learning more about the physiological underpinnings of HRV, available technologies, best practices and applications, I put together this deck recently that I hope you can find useful - unfortunately there is still much confusion out there: - Next time you have concerns or doubts, please contact us as we do our best to answer to everyone and explain these different aspects. Have a nice week.


App Privacy

The developer, A.S.M.A. B.V., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Linked to You

The following data may be collected and linked to your identity:

  • Sensitive Info

Data Not Linked to You

The following data may be collected but it is not linked to your identity:

  • Health & Fitness
  • Location
  • Contact Info
  • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    Up to six family members can use this app with Family Sharing enabled.

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