HRV4Training vs Williams Pace...
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
HRV4Training
Quantify stress, balance training and lifestyle, and improve performance with scientifically validated heart rate variability insights. This app accurately assesses HRV using your phone's camera or compatible devices, offering actionable interpretations for optimizing your training plan.
- HRV-based stress quantification
- Training and lifestyle balance
- Performance improvement insights
- Camera-based HRV assessment
- Integration with wearables
- Training load analysis
- VO2max and Lactate Threshold estimation
Read full descriptionHide full description
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, 15, 15 Max, 15 Pro, 16, 16 Max, 16 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, Oura, Strava and Coros 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.). HRV4Training does not provide medical advice. It is intended for informational purposes only. Consult a medical professional before making health or lifestyle decisions. Please find an overview of the relevant scientific literature in our guide, here: https://marcoaltini.substack.com/p/the-ultimate-guide-to-heart-rate
Williams Pace...
This app calculates running paces using methods developed by a legendary coach. It helps runners of all levels train effectively for road and track events, drawing on decades of proven performance-enhancing techniques.
- Pace calculation for road and track
- Based on legendary coach's methods
- Training for world-class runners
- Developed by a Bowerman protégé
- Helps break performance barriers
Read full descriptionHide full description
The Williams Pace Calculator © App is the latest digital version of the road and track running pace calculator that Bill Bowerman, the legendary coach and NIKE co-founder, used for training world-class runners at the University of Oregon and for the Olympic Games. His renowned ‘Men of Oregon’ athletes broke performance barriers, winning a total of 4 NCAA Team Championships and 24 NCAA individual titles. Now Bob Williams, one of the Bowerman protégé, brings you the know-how of pace calculation to you!
Screenshots
Verdict
The clearest difference is rating: Williams Pace... at 4.5 against HRV4Training's 3.6. Williams Pace... also leads on review sentiment (88% vs 61%) and price ($4.99 vs $9.99). HRV4Training's advantage is ratings volume (288 vs 17) and chart position (#9 vs #198). On update cadence, ads, in-app purchases and monetization model 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
HRV4Training costs $9.99 and Williams Pace... $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Williams Pace... holds the better App Store score, 4.5 against 3.6. That said, the two scores are not equally well evidenced: HRV4Training has 288 ratings behind it against 17, so its average is the more settled of the two. Written reviews point the same way: 61% of HRV4Training's written reviews are positive against 88% of Williams Pace...'s.
HRV4Training ships an update every 6 weeks, Williams Pace... monthly. The most recent releases landed on September 24, 2026 and September 10, 2026 respectively.
| Parameter | HRV4Training | Williams Pace... |
|---|---|---|
| Price | $9.99 | $4.99 — better |
| Rating | 3.6 (288 ratings) | 4.5 (17 ratings) — better |
| Positive reviews | 61.2% of reviews | 87.5% of reviews — better |
| Number of ratings | 288 — better | 17 |
| Update frequency | Every 6 weeks | Monthly — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Paid |
| Best chart rank | #9 — better | #198 |
| Devices | iPhone, iPod | iPhone, iPad, iPod — better |
| Requires iOS | 15.6 | 14.5 — better |
| Further details — not scored | ||
| Size | 35 MB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | A.S.M.A. B.V. | Robert E Williams |
Customer experience
HRV4Training
Williams Pace...
Bugs and requests
HRV4Training
Reported bugs
3 issues- App crashes frequently, especially with iOS updates
- Syncing issues with Strava, TrainingPeaks, and Apple Health
- Camera-based measurements often unreliable or inconsistent
Requested features
4 requests- Allow multiple measurements per day
- Improve integration with Apple Watch and other wearables
- Add more customization options and data visualization
- Expand support for non-athletic use cases
Williams Pace...
Not enough reviews yet to summarise bugs or requests.
In-app purchases
HRV4Training
No in-app purchases
Williams Pace...
No in-app purchases









