# ACLS Fast vs Diagnosaurus® DDx

The clearest difference is price: Diagnosaurus® DDx at Free against ACLS Fast's $3.99. Diagnosaurus® DDx also leads on rating (4.8 vs 2.8) and ratings volume (2.5K vs 4). ACLS Fast's advantage is in-app purchases (none vs 1) and review sentiment (76% vs 53%). On ads and device support there is nothing between them.

Diagnosaurus® DDx is free to download; ACLS Fast costs $3.99 up front. Diagnosaurus® DDx sells 1 one-off in-app purchase. ACLS Fast asks for nothing beyond the download.

Diagnosaurus® DDx holds the better App Store score, 4.8 against 2.8. That said, the two scores are not equally well evidenced: Diagnosaurus® DDx has 2.5K ratings behind it against 4, so its average is the more settled of the two. Written reviews complicate that: 76% of ACLS Fast's written reviews are positive against 53% of Diagnosaurus® DDx's, so the app with the better star average is not the one people write more warmly about.

ACLS Fast ships an update every 3 months, Diagnosaurus® DDx every 10 months. Both last shipped on October 26, 2026.

## The numbers

| Metric | ACLS Fast | Diagnosaurus® DDx |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | [2.8 (4 ratings)](https://appshunter.io/ios/app/acls-fast/id654570275/reviews) | **[4.8 (2.5K ratings)](https://appshunter.io/ios/app/diagnosaurus-ddx/id833728910/reviews)** |
| Number of ratings | 4 | **2.5K** |
| Positive reviews | **75.8% of reviews** | 53.2% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 10 months |
| Monetization | **Free** | Free with in-app purchases |
| Size | 20 MB | 19 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | iPhone, iPad, iPod | **iPhone, iPad, iPod, Mac** |
| Age rating | 17+ | 17+ |
| Developer | [Crystal Clear Solutions](https://appshunter.io/developer/444062170) | [Unbound Medicine, Inc.](https://appshunter.io/developer/300420400) |

## What reviewers say

### ACLS Fast

[App page](https://appshunter.io/ios/app/acls-fast/id654570275)

This app provides rapid guidance for ACLS 2020 guidelines, helping users quickly determine appropriate therapies through a question-based system. It includes information on rhythms, arrhythmias, acute coronary and stroke syndromes, and features a two-minute timer for code management.

**Highlights:** Question-based therapy guidance, Rhythms and arrhythmias management, Acute coronary and stroke syndrome protocols, Two-minute code timer with alarm, Interactive multiple-choice exams, Rapid diagnosis and treatment support

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

**In-app purchases:** none


### Diagnosaurus® DDx

[App page](https://appshunter.io/ios/app/diagnosaurus-ddx/id833728910)

This medical reference tool assists healthcare professionals in performing differential diagnoses quickly and confidently. It offers a searchable database of over 1,000 diagnoses, cross-referenced for related conditions, and allows users to save favorite entries and make custom notes.

**Highlights:** Over 1,000 differential diagnoses, Search by organ system, symptom, or disease, See Related DDx feature, Save favorite entries, Highlight and make custom notes, Universal Index Search

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Diagnosaurus DDx | $4.99 | one-time |

**What reviewers like**

- 👍 User-friendly interface
- 🚀 Quick access to differential diagnoses
- 💡 Helpful for building differential diagnoses
- 👍 Comprehensive coverage of conditions
- 👍 Useful for medical students and practitioners

**What reviewers complain about**

- 🐛 Lack of in-depth information
- 🐛 Incomplete differential diagnoses
- 🐛 Lack of links to explain conditions
- 🐛 Requires in-app purchase to access full content
- 🐛 Unreliable update mechanism

**Reported bugs**

- Subscription issues and inability to restore purchases
- Blank pages and non-functional content
- Compatibility issues with newer iOS versions

**Requested features**

- Add ability to edit or add custom differential diagnoses
- Improve search functionality and navigation
- Provide more detailed information on conditions
- Integrate with other medical resources and databases
- Improve support for older devices and iOS versions


## Frequently asked questions

### Is ACLS Fast free?

ACLS Fast costs $3.99, with no in-app purchases.

### Is Diagnosaurus® DDx free?

Diagnosaurus® DDx is free to download, with in-app purchases available.

### Which has better reviews, ACLS Fast or Diagnosaurus® DDx?

Diagnosaurus® DDx is rated higher. ACLS Fast averages 2.8 out of 5 from 4 ratings, while Diagnosaurus® DDx averages 4.8 from 2.5K ratings.

### Do ACLS Fast or Diagnosaurus® DDx have ads?

Neither ACLS Fast nor Diagnosaurus® DDx shows ads.

### Which is updated more often, ACLS Fast or Diagnosaurus® DDx?

ACLS Fast ships an update every 3 months, and Diagnosaurus® DDx every 10 months. Most recently, ACLS Fast was updated on October 26, 2026 and Diagnosaurus® DDx on October 26, 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.*