# CathSource vs ECHO On

The clearest difference is review sentiment: ECHO On at 100% against CathSource's 43%. ECHO On also leads on rating (4.9 vs 1.6) and monetization model (free vs paid). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ECHO On holds the better App Store score, 4.9 against 1.6. Both are backed by a comparable volume of ratings — 23 and 14 respectively. Written reviews point the same way: 43% of CathSource's written reviews are positive against 100% of ECHO On's.

CathSource ships an update every 2 months, ECHO On weekly. The most recent releases landed on October 6, 2026 and September 28, 2026 respectively.

## The numbers

| Metric | CathSource | ECHO On |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [1.6 (23 ratings)](https://appshunter.io/ios/app/cathsource/id420847275/reviews) | **[4.9 (14 ratings)](https://appshunter.io/ios/app/echo-on/id1519707786/reviews)** |
| Number of ratings | **23** | 14 |
| Positive reviews | 42.9% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Weekly** |
| Monetization | Paid | **Free** |
| Size | 79 MB | 414 MB |
| Requires iOS | 18.5 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 12+ | 12+ |
| Developer | [ECGsource LLC](https://appshunter.io/developer/377139096) | [Robert Arrigo](https://appshunter.io/developer/1519707788) |

## 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


### ECHO On

[App page](https://appshunter.io/ios/app/echo-on/id1519707786)

This medical education app helps users learn Transesophageal Echocardiography with a question bank, cognitive aid, case log, and reference library. It provides guidance on performing and interpreting a standard 28-view exam, including anatomy, function, and Doppler interrogations.

**Highlights:** Transesophageal Echocardiography education, Enlarging question bank, Rescue TEE cognitive aid, Case Log system, Perioperative Quick Reference library, Offline echo loops, Pathology, technique, and normal loop examples

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is CathSource free?

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

### Is ECHO On free?

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

### Which has better reviews, CathSource or ECHO On?

ECHO On is rated higher. CathSource averages 1.6 out of 5 from 23 ratings, while ECHO On averages 4.9 from 14 ratings.

### Do CathSource or ECHO On have ads?

Neither CathSource nor ECHO On shows ads.

### Which is updated more often, CathSource or ECHO On?

CathSource ships an update every 2 months, and ECHO On weekly. Most recently, CathSource was updated on October 6, 2026 and ECHO On on September 28, 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.*