# CathSource vs EP Calipers

The clearest difference is price: CathSource at Free against EP Calipers's $1.99. CathSource also leads on ratings volume (23 vs 6). EP Calipers's advantage is rating (2.3 vs 1.6) and chart position (#186 vs unranked). On review sentiment, update cadence, ads and in-app purchases there is nothing between them.

CathSource is free to download; EP Calipers costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

EP Calipers holds the better App Store score, 2.3 against 1.6. Both are backed by a comparable volume of ratings — 23 and 6 respectively. Written reviews point the same way: 43% of CathSource's written reviews are positive against 50% of EP Calipers's.

CathSource ships an update every 2 months, EP Calipers every 3 months. The most recent releases landed on September 18, 2026 and September 13, 2026 respectively.

## The numbers

| Metric | CathSource | EP Calipers |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| Rating | [1.6 (23 ratings)](https://appshunter.io/ios/app/cathsource/id420847275/reviews) | **[2.3 (6 ratings)](https://appshunter.io/ios/app/ep-calipers/id982313078/reviews)** |
| Number of ratings | **23** | 6 |
| Positive reviews | 42.9% of reviews | **50.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 3 months |
| Monetization | Paid | Paid |
| Best chart rank | — | **#186** |
| Size | 79 MB | 9 MB |
| Requires iOS | 18.5 | **14.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 12+ | 12+ |
| Developer | [ECGsource LLC](https://appshunter.io/developer/377139096) | [EP Studios](https://appshunter.io/developer/574231798) |

## What reviewers say

### CathSource

[App page](https://appshunter.io/ios/app/cathsource/id420847275)

A comprehensive medical reference focused on cardiac catheterization and angiography. It offers a searchable index of specialized topics, a database of videos of common and rare findings, and a collection of images including hemodynamic formulas and tables.

**Highlights:** Searchable index of cardiac catheterization topics, Database of coronary angiogram, ventriculogram, and aortogram videos, Image database with hemodynamic formulas and tables, Covers common and rare cardiovascular pathologies, Developed by practicing Interventional Cardiologists

**Features:** macOS Compatibility

**In-app purchases:** none


### EP Calipers

[App page](https://appshunter.io/ios/app/ep-calipers/id982313078)

**Currently charting:** #186 Top Paid · Medical (US App Store)

This medical app allows users to measure intervals and angles on electrocardiogram (ECG) images. It's designed for healthcare professionals to accurately analyze ECGs from photos or PDFs, aiding in calculations like heart rate and QT intervals.

**Highlights:** Measure ECG intervals, Measure ECG angles, Calculate mean heart rate, Determine corrected QT interval, Analyze ECG photos and PDFs, Supports Brugada syndrome beta angle measurement

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is CathSource free?

CathSource is free to download, with no in-app purchases.

### Is EP Calipers free?

EP Calipers costs $1.99, with no in-app purchases.

### Which has better reviews, CathSource or EP Calipers?

EP Calipers is rated higher. CathSource averages 1.6 out of 5 from 23 ratings, while EP Calipers averages 2.3 from 6 ratings.

### Do CathSource or EP Calipers have ads?

Neither CathSource nor EP Calipers shows ads.

### Which is updated more often, CathSource or EP Calipers?

CathSource ships an update every 2 months, and EP Calipers every 3 months. Most recently, CathSource was updated on September 18, 2026 and EP Calipers on September 13, 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.*