Comparison

CNS Tap Test vs HRV4Training

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

CNS Tap Test

This app measures central nervous system (CNS) status using a finger tapping test. Track your performance over time to identify optimal training days or potential fatigue, sickness, or injury.

Highlights
  • Measures central nervous system status
  • Tracks finger tapping speed
  • Establishes baseline performance
  • Identifies CNS fatigue
  • Graphs and saves test results
  • Allows for multiple daily samples
Features
Read full description

As featured in the book Beyond Training by Ben Greenfield. As featured in the podcasts: - Harder to Kill Radio 026 - Ameer Rosic Optimal Health Show #58 - Ben Greenfield Fitness #263 CNS Tap Test is an adaptation of the Finger Tap Test (FTT) or Finger Oscillation Test (FOT) which is used to measure the status of the central nervous system (CNS), and is one of the most commonly used tests in neuropsychology, because of its simplicity and reliability, and because it generates relevant data about fine motor control, which is based on motor speed as well as kinesthetic and visual-motor ability. The application should be used on a regular basis to determine an athlete’s baseline. If the CNS Tap Test result is elevated it is suitable for a maximum effort or a heavy lifting day. If the CNS Tap Test result is lower than average it may indicate CNS fatigue and impending sickness, injury or over-training. Both hands should be tested on a regular basis in a consistent environment, typically every morning on waking. The procedure for testing is: - Rest hand palm down on the heel of the hand on a flat surface - Tapping is done with the index (pointing finger), and all other fingers remain on the flat surface - The timer starts with the first tap - When the timer expires no further taps will be accepted - The result can either be saved or discarded. Multiple samples can be saved per day. The resulting data can be graphed, emailed or managed from within CNS Tap Test. Using Swift Charts for improved accessibility and legibility.

About

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.

Highlights
  • 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
Features
Read 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

Screenshots

CNS Tap Test4 screens
HRV4Training4 screens

Verdict

The call

The clearest difference is rating: CNS Tap Test at 4.6 against HRV4Training's 3.6. CNS Tap Test also leads on price ($1.99 vs $9.99). HRV4Training's advantage is chart position (#66 vs unranked) and update cadence (every 6 weeks vs every 3 months). On review sentiment, ratings volume, ads and in-app purchases 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

CostPrice · In-app purchases · Ads · Monetization

CNS Tap Test costs $1.99 and HRV4Training $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

CNS Tap Test holds the better App Store score, 4.6 against 3.6. Both are backed by a comparable volume of ratings — 277 and 288 respectively. Written reviews point the same way: 69% of CNS Tap Test's written reviews are positive against 61% of HRV4Training's.

UpkeepUpdate frequency

CNS Tap Test ships an update every 3 months, HRV4Training every 6 weeks. The most recent releases landed on October 16, 2026 and October 17, 2026 respectively.

Scorecard5 real differences · 6 level
CNS Tap Test versus HRV4Training: the parameters behind the verdict, then further details
ParameterCNS Tap TestHRV4Training
Price$1.99 — better$9.99
Rating4.6 (277 ratings) — better3.6 (288 ratings)
Positive reviews68.8% of reviews — better61.2% of reviews
Number of ratings277288 — better
Update frequencyEvery 3 monthsEvery 6 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree — betterPaid
Best chart rank—#66 — better
DevicesiPhoneiPhone, iPod — better
Requires iOS16.015.6 — better
Further details — not scored
Size4 MB35 MB
Age rating4+4+
Developersmudge.io PTY LTDA.S.M.A. B.V.

Customer experience

CNS Tap Test

All ratings277 ratings
Positive89.9%
Neutral3.6%
Negative6.5%
Written reviews32 reviews
Positive68.8%
Neutral9.4%
Negative21.9%

HRV4Training

All ratings288 ratings
Positive62.2%
Neutral5.6%
Negative32.3%
Written reviews451 reviews
Positive61.2%
Neutral7.3%
Negative31.5%

User reviews

CNS Tap Test

From 277 App Store ratings

What we love

  • 👍 Simple and direct to use
  • 👍 Easy to use
  • 👍 Great app for monitoring recovery
  • 👍 Effective CNS testing tool
  • 👍 Useful for assessing neural fatigue

Room to improve

  • 😞 Confusing interface
  • 😞 Plain and not very useful
  • 😞 No real information provided
  • 😞 Not worth buying
  • 😞 Data export issues

HRV4Training

From 288 App Store ratings

What we love

  • 👍 Accurate HRV measurements
  • 🚀 Straightforward and easy to use
  • 💡 Provides valuable insights for training and recovery
  • 👍 Integrates well with other fitness apps
  • 👍 Responsive and helpful developer support

Room to improve

  • 🐛 Inconsistent readings and technical issues
  • 🔒 Requires user account and data sharing
  • 🔒 Concerns about data privacy
  • 🔋 Drains battery when using camera for measurements

Bugs and requests

CNS Tap Test

Reported bugs

1 issue
  • Cannot port data when switching iPhones

Requested features

11 requests
  • Add time of day to graphs
  • Set parameters on graph
  • Integrate data from sleep/step trackers
  • Sync with calendar
  • Option for 'best out of 3'
Show 6 more
  • Daily average option
  • Record more than 1 test per day
  • Allow unlimited tests per day
  • Include time (of day) in data export
  • Put date in ISO standard: yyyy-mm-dd
  • Reminders

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

In-app purchases

None

CNS Tap Test

No in-app purchases

None

HRV4Training

No in-app purchases

Questions

Is CNS Tap Test free?
CNS Tap Test costs $1.99, with no in-app purchases.
Is HRV4Training free?
HRV4Training costs $9.99, with no in-app purchases.
Which has better reviews, CNS Tap Test or HRV4Training?
CNS Tap Test is rated higher. CNS Tap Test averages 4.6 out of 5 from 277 ratings, while HRV4Training averages 3.6 from 288 ratings.
Do CNS Tap Test or HRV4Training have ads?
Neither CNS Tap Test nor HRV4Training shows ads.
Which is updated more often, CNS Tap Test or HRV4Training?
CNS Tap Test ships an update every 3 months, and HRV4Training every 6 weeks. Most recently, CNS Tap Test was updated on October 16, 2026 and HRV4Training on October 17, 2026.

Other comparisons