Comparison

Heart Rate Variability Logger vs mySASY training

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

Head to head
About

Heart Rate Variability Logger

This app records, plots, and exports heart rate variability data, including time, frequency, and non-linear features. It supports experience sampling, RR-interval correction, and activity/location tracking. Requires a compatible Bluetooth heart rate sensor.

Highlights
  • Record and plot HRV data
  • Extract time and frequency domain features
  • Experience sampling for event annotation
  • Compare multiple recordings
  • Activity and location tracking
  • RR-interval correction
  • Export data for Kubios
Features
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Heart Rate Variability Logger lets you record, plot and export time, frequency and non-linear HRV Features (includes experience sampling, RR-interval correction, DFA alpha 1 for aerobic threshold estimation in real-time, comparison between recordings, activity monitoring & step counting, location tracking). Heart Rate Variability Logger requires a Bluetooth Low Energy (also called Bluetooth Smart or BLE or 4.0) heart rate sensor (we recommend Polar H7 or H10) Main features: - Extracts, plots, stores and exports heart rate, rr-intervals, time and frequency domain heart rate variability features (AVNN, SDNN, rMSSD, pNN50, LF, HF, LF/HF, alpha 1 from DFA) - Configurable experience sampling for events annotation - Comparison between up to 3 recordings lets you get a better understanding of differences in HRV under different contexts in a glance. The comparison modality includes also Outlier removal - Activity tracking: step counter or accelerometer derived motion intensity for user context (step counter only for iPhones 5S) - Location tracking, either using GSM/WiFi networks (low battery consumption) or GPS (high accuracy) - Configurable time window for features computation (choose between 30 seconds, 1, 2 or 5 minutes) - RR-intervals correction can be enabled to prevent ectopic beats or artifacts from affecting HRV features - export for Kubios - Filters data based on the selected threshold - Shows HR in the app icon - Data export using iTunes or Dropbox - Tested for recordings longer than 24 hours Please note that continued use of GPS running in the background can dramatically decrease battery life.

About

mySASY training

Optimize your athletic performance with science-backed diagnostics. Monitor your body's readiness for training, identify optimal days for increased load, and prevent overtraining. Achieve your ambitious goals by training smarter, not just harder.

Highlights
  • Morning adaptation capacity diagnostics
  • Monitor body readiness for training
  • Identify days for increased training load
  • Detect negative body reactions
  • Prevent overtraining and fatigue
  • Improve training quality over quantity
Features
Read full description

The ultimate tool for achieving ambicious training goals of any athlete. It shows you the morning state of your adaptation capacity by science proved diagnostics. Do you have ambitious training goals? Do you want to achieve high training efficiency and avoid health complications? Are you an amateur athlete who trains to the maximum but needs to combine training with work? mySASY will help you with that Thanks to the connection between science (science article) and practice, the morning diagnostics of mySASY will allow you to clearly monitor with maximum accuracy: -- which days is your body ready for further training, -- which days should you increase the training load because your body is uspercompensating, , -- which days your body's reaction is negative and you need to focus on the previous regimen to identify the cause and improve further. By working with mySASY for a long time, you gain control over your performance, prevent the accumulation of central fatigue (overtraining) and improve the quality of your training compared to the quantity for which you probably still do not have more time. You will discover a completely new dimension of training that will help you achieve your sports goals. You need an HRM chest monitor to measure in mySASY training. In the application, it is possible to buy it with a 33% percentage discount for 24 hours from registration with a 30-day money back guarantee. You can use the trial version of the application for free 14 days after registration. Apple Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy policy: https://eshop.mysasy.com/prohlaseni-gdpr?utm_source=ios

Screenshots

Heart Rate Variability Logger4 screens
mySASY training4 screens

Verdict

The call

The clearest difference is price: mySASY training at Free against Heart Rate Variability Logger's $9.99. mySASY training also leads on review sentiment (71% vs 43%). Heart Rate Variability Logger's advantage is in-app purchases (none vs 7) and chart position (#60 vs unranked). On ads, device support and iOS requirement 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

mySASY training is free to download; Heart Rate Variability Logger costs $9.99 up front. mySASY training sells 7 in-app purchases, starting at $0.49 per month. Heart Rate Variability Logger asks for nothing beyond the download.

UpkeepUpdate frequency

Heart Rate Variability Logger ships an update fortnightly, mySASY training monthly. The most recent releases landed on October 26, 2026 and October 25, 2026 respectively.

Scorecard6 real differences · 5 level
Heart Rate Variability Logger versus mySASY training: the parameters behind the verdict, then further details
ParameterHeart Rate Variability LoggermySASY training
Price$9.99Free — better
Rating3.5 (19 ratings) — better—
Positive reviews43.1% of reviews71.4% of reviews — better
Number of ratings19 — better—
Update frequencyFortnightly — betterMonthly
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
Best chart rank#60 — better—
DevicesiPhone, iPod, Apple Watch — betteriPhone, iPod
Requires iOS15.614.2 — better
Further details — not scored
Size10 MB19 MB
Age rating4+4+
DeveloperA.S.M.A. B.V.mySASY a.s.

Customer experience

Heart Rate Variability Logger

All ratings19 ratings
Positive63.2%
Neutral0.0%
Negative36.8%
Written reviews58 reviews
Positive43.1%
Neutral6.9%
Negative50.0%

mySASY training

Written reviews35 reviews
Positive71.4%
Neutral2.9%
Negative25.7%

In-app purchases

None

Heart Rate Variability Logger

No in-app purchases

7 purchases

mySASY training

Subscriptions7
  • Free$0.491 Month
  • Basic+ 1 month$10.991 Month
  • Sport 1 month$14.491 Month
Show 4 more
  • Basic+ 6 months$53.996 Months
  • Sport 6 months$71.996 Months
  • Basic+ 12 months$79.991 Year
  • Sport 12 months$118.991 Year

Questions

Is Heart Rate Variability Logger free?
Heart Rate Variability Logger costs $9.99, with no in-app purchases.
Is mySASY training free?
mySASY training is free to download, with in-app purchases available.
Do Heart Rate Variability Logger or mySASY training have ads?
Neither Heart Rate Variability Logger nor mySASY training shows ads.
Which is updated more often, Heart Rate Variability Logger or mySASY training?
Heart Rate Variability Logger ships an update fortnightly, and mySASY training monthly. Most recently, Heart Rate Variability Logger was updated on October 26, 2026 and mySASY training on October 25, 2026.

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