# Diagnosaurus® DDx vs MobilEM

The clearest difference is rating: Diagnosaurus® DDx at 4.8 against MobilEM's 3.6. Diagnosaurus® DDx also leads on ratings volume (2.5K vs 39) and review sentiment (53% vs 45%). MobilEM's advantage is update cadence (every 2 months vs every 10 months) and chart position (#67 vs unranked). On price, ads, in-app purchases and monetization model there is nothing between them.

Both are free to download. Diagnosaurus® DDx sells 1 one-off in-app purchase and MobilEM sells 12 in-app purchases, starting at $1.99 per year. Whichever you choose, the download price is not the number that matters.

Diagnosaurus® DDx holds the better App Store score, 4.8 against 3.6. That said, the two scores are not equally well evidenced: Diagnosaurus® DDx has 2.5K ratings behind it against 39, so its average is the more settled of the two. Written reviews point the same way: 53% of Diagnosaurus® DDx's written reviews are positive against 45% of MobilEM's.

Diagnosaurus® DDx ships an update every 10 months, MobilEM every 2 months. Both last shipped on October 23, 2026.

## The numbers

| Metric | Diagnosaurus® DDx | MobilEM |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (2.5K ratings)](https://appshunter.io/ios/app/diagnosaurus-ddx/id833728910/reviews)** | [3.6 (39 ratings)](https://appshunter.io/ios/app/mobilem/id1474834329/reviews) |
| Number of ratings | **2.5K** | 39 |
| Positive reviews | **53.2% of reviews** | 45.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 10 months | **Every 2 months** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Best chart rank | — | **#67** |
| Size | 19 MB | 205 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad, iPod |
| Age rating | 17+ | 17+ |
| Developer | [Unbound Medicine, Inc.](https://appshunter.io/developer/300420400) | [Emergency Medicine Residents' Association](https://appshunter.io/developer/331670150) |

## What reviewers say

### 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


### MobilEM

[App page](https://appshunter.io/ios/app/mobilem/id1474834329)

**Currently charting:** #67 Top Grossing · Medical (US App Store)

Provides fast, evidence-based clinical guidance for emergency medicine professionals. Access updated recommendations on a wide range of topics, including antibiotics, toxicology, and critical care. Offers free content, individual purchases, and an all-access subscription.

**Highlights:** Evidence-based recommendations, Antibiotic and toxicology guidance, EKG and orthopedic injury protocols, Airway and pediatric emergency management, Critical care medication information, Fast navigation and universal search, Bookmarking and note-taking

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

**In-app purchases (12)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Ventilator Mgmt. Subscription | $1.99 | per year |
| Pediatric Qwic | $1.99 | per year |
| MobilEm Airway Management | $4.99 | per year |
| Trauma Guide | $4.99 | per year |
| Antibiotic Guide Subscription | $9.99 | per year |
| MobilEm Ortho Guide | $9.99 | per year |
| MobilEM Tox Guide | $9.99 | per year |
| PressorDex | $9.99 | per year |
| EKG Guide Subscription | $9.99 | per year |
| Pain Management | $9.99 | per year |
| PEM Fundamentals Subscription | $9.99 | per year |
| MobilEm All Access Pass | $39.99 | per year |


## Frequently asked questions

### Is Diagnosaurus® DDx free?

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

### Is MobilEM free?

MobilEM is free to download, with in-app purchases available.

### Which has better reviews, Diagnosaurus® DDx or MobilEM?

Diagnosaurus® DDx is rated higher. Diagnosaurus® DDx averages 4.8 out of 5 from 2.5K ratings, while MobilEM averages 3.6 from 39 ratings.

### Do Diagnosaurus® DDx or MobilEM have ads?

Neither Diagnosaurus® DDx nor MobilEM shows ads.

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

Diagnosaurus® DDx ships an update every 10 months, and MobilEM every 2 months. Most recently, Diagnosaurus® DDx was updated on October 23, 2026 and MobilEM on October 23, 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.*