# ECG Books vs arrhythmia

The clearest difference is review sentiment: ECG Books at 91% against arrhythmia's 44%. ECG Books also leads on monetization model (free with in-app purchases vs subscription) and rating (4.7 vs 4.1). On price, ratings volume, update cadence and ads there is nothing between them.

Both are free to download. ECG Books sells 10 one-off in-app purchases and arrhythmia sells 3 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

ECG Books holds the better App Store score, 4.7 against 4.1. Both are backed by a comparable volume of ratings — 159 and 113 respectively. Written reviews point the same way: 91% of ECG Books's written reviews are positive against 44% of arrhythmia's.

ECG Books ships an update monthly, arrhythmia every 3 weeks. Both last shipped on October 24, 2026.

## The numbers

| Metric | ECG Books | arrhythmia |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (159 ratings)](https://appshunter.io/ios/app/ecg-books/id739003604/reviews)** | [4.1 (113 ratings)](https://appshunter.io/ios/app/arrhythmia/id996560473/reviews) |
| Number of ratings | **159** | 113 |
| Positive reviews | **90.9% of reviews** | 43.9% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 3 weeks** |
| Monetization | **Free with in-app purchases** | Subscription |
| Size | 44 MB | 159 MB |
| Requires iOS | **10.0** | 17.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Mac |
| Age rating | 12+ | 17+ |
| Developer | [WMS, Inc](https://appshunter.io/developer/471623357) | [Single Sail Software, LLC](https://appshunter.io/developer/359715495) |

## What reviewers say

### ECG Books

[App page](https://appshunter.io/ios/app/ecg-books/id739003604)

Access a vast library of real-world ECG recordings demonstrating various cardiac abnormalities. Learn to interpret ECG findings with concise explanations and detailed case studies. Practice with over 1000 abnormal ECG cases in movie or report modes.

**Highlights:** View real-time ECG recordings, Concise explanations of abnormalities, 1000+ abnormal ECG cases, Movie mode with heartbeat sounds, Report mode for measurement and sharing, Detailed information on causes, diagnosis, and treatment

**Features:** Vision Pro support

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| AF With RVR Book | $0.99 | one-time |
| Atrial Flutter Book | $1.99 | one-time |
| Long QT Prolongation Book | $1.99 | one-time |
| Pace Maker Book | $1.99 | one-time |
| First-degree Atrioventricular Book | $1.99 | one-time |
| II Degree AV Block Book | $1.99 | one-time |
| ST Elevation Book | $1.99 | one-time |
| Pulmonary Heart Disease Book | $2.99 | one-time |
| VT Book | $2.99 | one-time |
| ECG BOOKS PRO BUNDLE | $9.99 | one-time |

**What reviewers like**

- 👍 Detailed ECG explanations
- 🚀 Comprehensive ECG library
- 🤓 Helpful for learning and refreshing ECG knowledge
- 💡 Live ECG rhythm demonstrations
- 🎓 Great resource for medical/nursing students

**What reviewers complain about**

- 🐛 Occasional crashes or compatibility issues
- 💰 Paid version required to unlock full content
- 🔍 Could use more in-depth explanations for beginners
- 🤔 Some typos or minor issues in descriptions

**Reported bugs**

- Login/sync issues between devices
- Compatibility problems with newer iOS versions

**Requested features**

- Add more ECG cases and examples
- Include a quiz or practice mode
- Improve font size and readability
- Introduce a free trial or more sample content


### arrhythmia

[App page](https://appshunter.io/ios/app/arrhythmia/id996560473)

Practice interpreting EKGs in lead II with realistic simulations. Choose rhythms to study or test your knowledge in a game mode. Ideal for healthcare professionals to hone their diagnostic skills.

**Highlights:** EKG interpretation practice, Lead II simulation, Study Mode with rhythm selection, Game Mode for random rhythm identification, Customizable rhythm sets, Realistic rhythm variations

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly | $2.99 | per month |
| Yearly | $19.99 | per year |
| Unlock All Rhythms (One-time Purchase) | $4.99 | one-time |

**What reviewers like**

- 👍 Great study tool for EKGs
- 👍 Helpful for understanding EKGs
- 👍 Good for practicing rhythm recognition
- 👍 Interactive and colorful design
- 👍 Dynamic testing

**What reviewers complain about**

- 👎 Immediately asks for paid version
- 👎 Missing common and important rhythms
- 👎 Rhythms are unrealistic
- 👎 Cannot try before signing up
- 👎 Clunky and slow horizontal scrolling

**Reported bugs**

- App no longer works after iOS update
- App does not work on Apple Watch

**Requested features**

- Add more common and important rhythms (torsades, WPW, STEMI, accelerated/tachycardic idioventricular, WAP, MAT)
- Option to read as a 12-lead instead of a single rhythm line
- Add variations to rhythms
- Add Left Bundle Branch Block
- Add a 12-lead option


## Frequently asked questions

### Is ECG Books free?

ECG Books is free to download, with in-app purchases available.

### Is arrhythmia free?

arrhythmia is free to download, with in-app purchases available.

### Which has better reviews, ECG Books or arrhythmia?

ECG Books is rated higher. ECG Books averages 4.7 out of 5 from 159 ratings, while arrhythmia averages 4.1 from 113 ratings.

### Do ECG Books or arrhythmia have ads?

Neither ECG Books nor arrhythmia shows ads.

### Which is updated more often, ECG Books or arrhythmia?

ECG Books ships an update monthly, and arrhythmia every 3 weeks. Most recently, ECG Books was updated on October 24, 2026 and arrhythmia on October 24, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*