# CathSource vs Cardio Shock

The clearest difference is review sentiment: Cardio Shock at 100% against CathSource's 38%. Cardio Shock also leads on rating (5.0 vs 1.6) and monetization model (free vs paid). CathSource's advantage is ratings volume (23 vs 4). On price, update cadence, 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.

Cardio Shock holds the better App Store score, 5.0 against 1.6. That said, the two scores are not equally well evidenced: CathSource has 23 ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 38% of CathSource's written reviews are positive against 100% of Cardio Shock's.

CathSource ships an update every 2 months, Cardio Shock every 5 weeks. The most recent releases landed on October 18, 2026 and October 4, 2026 respectively.

## The numbers

| Metric | CathSource | Cardio Shock |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [1.6 (23 ratings)](https://appshunter.io/ios/app/cathsource/id420847275/reviews) | **[5.0 (4 ratings)](https://appshunter.io/ios/app/cardio-shock/id1439394483/reviews)** |
| Number of ratings | **23** | 4 |
| Positive reviews | 38.5% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 5 weeks** |
| Monetization | Paid | **Free** |
| Size | 79 MB | 7 MB |
| Requires iOS | 18.5 | **12.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 12+ | 17+ |
| Developer | [ECGsource LLC](https://appshunter.io/developer/377139096) | [Affan Haleem](https://appshunter.io/developer/1380371873) |

## 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


### Cardio Shock

[App page](https://appshunter.io/ios/app/cardio-shock/id1439394483)

This medical app calculates CPO and PAPi to help assess patient candidacy for mechanical support. It utilizes formulas based on research from The Detroit Shock Initiative to provide these critical medical calculations.

**Highlights:** CPO calculation, PAPi calculation, Mechanical support assessment, Based on Detroit Shock Initiative findings, BSA and Fick formulas

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is CathSource free?

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

### Is Cardio Shock free?

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

### Which has better reviews, CathSource or Cardio Shock?

Cardio Shock is rated higher. CathSource averages 1.6 out of 5 from 23 ratings, while Cardio Shock averages 5.0 from 4 ratings.

### Do CathSource or Cardio Shock have ads?

Neither CathSource nor Cardio Shock shows ads.

### Which is updated more often, CathSource or Cardio Shock?

CathSource ships an update every 2 months, and Cardio Shock every 5 weeks. Most recently, CathSource was updated on October 18, 2026 and Cardio Shock on October 4, 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.*