# Critical ABG vs VentilO

The clearest difference is review sentiment: VentilO at 100% against Critical ABG's 50%. VentilO also leads on price (Free vs $3.99) and rating (5.0 vs 4.0). Critical ABG's advantage is chart position (#66 vs unranked). On ratings volume, ads, in-app purchases and device support there is nothing between them.

VentilO is free to download; Critical ABG costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

VentilO holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 4 and 2 respectively. Written reviews point the same way: 50% of Critical ABG's written reviews are positive against 100% of VentilO's.

Critical ABG ships an update every 42 months, VentilO every 2 months. The most recent releases landed on September 24, 2026 and June 15, 2026 respectively.

## The numbers

| Metric | Critical ABG | VentilO |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | [4.0 (4 ratings)](https://appshunter.io/ios/app/critical-abg/id1438674467/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/ventilo/id1478758927/reviews)** |
| Number of ratings | **4** | 2 |
| Positive reviews | 50.0% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 42 months | **Every 2 months** |
| Monetization | Paid | **Free** |
| Best chart rank | **#66** | — |
| Size | 3 MB | 26 MB |
| Requires iOS | 15.2 | **13.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 17+ | 17+ |
| Developer | [The Barringer Group, LLC](https://appshunter.io/developer/504065735) | [Institut universitaire de cardiologie et de pneumologie de Quebec](https://appshunter.io/developer/576953454) |

## What reviewers say

### Critical ABG

[App page](https://appshunter.io/ios/app/critical-abg/id1438674467)

**Currently charting:** #66 Top Paid · Medical (US App Store)

This medical app provides a comprehensive analysis of acid-base disorders with a step-by-step approach to understanding them. It includes common causes, differential treatment options, and built-in compensation mechanisms. An optimization calculator for ventilator settings is also available.

**Highlights:** Acid-base disorder analysis, Step-by-step understanding, Common causes and treatments, Compensation mechanisms, Ventilation optimization calculator, Differential diagnosis

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

**In-app purchases:** none


### VentilO

[App page](https://appshunter.io/ios/app/ventilo/id1478758927)

This educational app helps healthcare professionals manage patients on mechanical ventilation. It provides guidance on setting initial parameters, optimizing settings for oxygenation and CO2 elimination, and understanding the impact of dead space. It also includes tools for calculating various respiratory parameters and links to additional resources.

**Highlights:** Initial ventilatory setting guidance, Parameter influence analysis, Optimization for oxygenation and CO2, Dead space impact education, Instrumental dead space calculation, Respiratory calculators, Links to additional tools

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Critical ABG free?

Critical ABG costs $3.99, with no in-app purchases.

### Is VentilO free?

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

### Which has better reviews, Critical ABG or VentilO?

VentilO is rated higher. Critical ABG averages 4.0 out of 5 from 4 ratings, while VentilO averages 5.0 from 2 ratings.

### Do Critical ABG or VentilO have ads?

Neither Critical ABG nor VentilO shows ads.

### Which is updated more often, Critical ABG or VentilO?

Critical ABG ships an update every 42 months, and VentilO every 2 months. Most recently, Critical ABG was updated on September 24, 2026 and VentilO on June 15, 2026.

---

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