Mobile Apps & Resources: Diagnosaurus DDx


To keep you updated on the go, our ‘app of the month’ highlights one free informational app every month!

Librarian reviewers consider the audience and purpose of the apps, as well as highlighting additional features:
  • In the ‘Evidence’ section, we assess how easily an app user can identify the app’s currency and support from the evidence
  • In the ‘Usability’ section, we assess the organization of information and other usability factors that may contribute to user experience

Our complete grading criteria for evidence and usability are embedded in the review.

Please note that the reviewers are not healthcare professionals, and so cannot appraise the quality of any recommendations within the app. The reviews are not endorsements.

View the AHS policy on Mobile Wireless Devices and Services.


Diagnosaurus DDx


Diagnosaurus DDx

Version reviewed

Android ; iPhone Diagnosaurus 4.0 (on Apple store listed as v1.8)

Device & OS used

Samsung, Android 4 ; iPhone X

Date of review

August 29, 2019 

Reviewers Mark Mueller & Shelley White
Technician Support Brandie Bailey



Image Source: Family Medicine Study Guide, Apple App Store. ​Retrieved on October 7, 2019 from:


Stated Purpose  

“Diagnosaurus® is a valuable quick reference tool that contains over 1,000 differential diagnoses. Available for iOS and Android, this application helps healthcare professionals reach accurate diagnoses with speed and confidence at the point of care.” From Unbound Medicine website. 

Diagnosaurus allows the user to provide differential diagnoses of symptoms, signs and diseases. Users can also view entries by organ system as well. Diagnosaurus also offers both etiology and differential diagnoses for various terms. Extremely limited view of topics in the “Free Preview” version of this app.


​Users can tag various entries and assign them to various needs in the point-of-care process. Users can also add sections to their favorites for later reference. There is also a Recent feature that saves the previous entries visited in earlier usage.



Physicians, residents, nurse practitioners, physician assistants, allied health professionals



Part 1: Editorial committee, content updates, and evidence grading

Author (Roni F. Zeiger, MD) and publisher information (McGraw-Hill Education) are listed on the app, the app stores’ and the website. There is no listing of any editorial, peer-review committee or institutional/organizational affiliations in any of the aforementioned sources.  As such, it is difficult to provide evidence grading to preview version of the Diagnosaurus app. 

Part 2: Source and authorship information for 3 entries

Links to relevant evidence s-based studies are only provided in the subscription version, however, they are not provided for the entries in the preview version of the app. The developer and author of the app (Dr. Roni F. Zeiger) earned his MD at Stanford University and completed his internal medicine residency at the University of California. According to the TEDMED website he has written extensively in the medical sciences and is an authority in social media and health.

Organization of information

There are four main sections: “All Entries”, “Organ Systems”, “Symptoms” and “Diseases”. The term in each section is listed alphabetically. Each term contains information on the etiology and differential diagnoses in the section DDX.

Extremely limited view and content of topics in the “Free Preview” version of this app. The subscribed version contains the complete list of entries. The subscribed version also contains outside references and more cross links to other conditions for each entry.


This App was very easy to navigate and was very intuitive. Users are able to browse entries in the four different categories alphabetically. Each entry has a related DDx entry for differential diagnoses. 

The free version of the App is extremely limited. To access most entries and the related DDx’s, users will have to purchase a subscription to the App.


User Account required: Yes

Internet connection required for use: No

Text search field: Yes

Browsable content: Yes 

Advertisements: No

Pop-up advertisements: No

In-app purchases: Yes

App requests access to the following on your device:
Phone: read phone status and identity
Device ID & call information: 
Identity: find accounts on the device
Device & app history: retrieve running apps
Contacts: find accounts on the device
Other: receive data from the internet, full network access, prevent device from sleeping, view network connections, Google Play license check


Compatible with iPhone, iPad and iPod touch.  Requires iOS 9.0 or later.  Last updated (as per App store listing): November 1, 2018

Compatible with Android 4.4 and up.  

Windows Mobile (All platforms)
Mb of available memory*
ActiveSync 4.0 or later (Win XP or earlier)
Windows Mobile Device Center (for MS Vista)
Memory cards are supported
Windows PC with internet connection  Last updated (as per Google Play listing): July 11, 2019


7.1 MB ; 17.2MB iPhone                                                                                                                                                         

App Developer

Roni F. Zeiger, MD

Country of Origin

United States


Roni F. Zeiger, MD:

Facebook: Head of Health Strategy McGraw-Hill Medical:

Unbound Medicine Inc.