Testing desktop, mobile and web applications: what’s the difference?

Software applications have seen exponential diversification over the past two decades, not only in terms of what can be done with the software but also in terms of how far applications can penetrate to reach end-users. For example, desktop applications like Microsoft Office® have now moved to web applications such as Office 365, while web applications like Amazon® have companion mobile applications. Among mobile applications, we have native mobile applications developed in Java or Kotlin (Android) or Swift (iOS) or hybrid which are basically javascript, HTML and CSS based apps which can be used on most mobile OS.

Testing each of these applications, whether it’s the same application on different platforms or a different application on different platforms, requires understanding the unique value of each platform, their functional and non-functional requirements, as well as the limitations and usability expectations from an end-user’s point of view. 

Mobile vs. Desktop vs. Web App Testing

Device compatibility

Web applications are more dependent on the browser and therefore, offer a degree of device independence. Web apps that are supported on mobile browsers, can be easily tested with the browser’s own built-in testing tools for different screen sizes. 

Mobile apps, both native and hybrid, need to be compatible with different devices. A good place to start is to pick the top three most used mobile phones and tablets (if the app is made for tablets) in the focus market. It’s worth remembering that as screen sizes change or as apps switch from portrait to landscape orientation, both the UI and the functional flow of the application can break.

Related: How many mobile device and OS combinations should you test?

Internet availability

Desktop and web applications are built with the premise that a steady wifi or ethernet connection is available. While major desktop apps can provide a large degree of functionality offline, web applications are entirely dependent on an internet connection being available. Mobile apps are somewhere in between – limited functionality can be provided offline e.g. in some games, and then synced with servers once internet connectivity is available. In this instance, testing scenarios to ensure acceptance criteria are met would include verifying that users are not able to: 

  • score extra game points by going offline and coming back online
  • place successful orders in a closed cart
  • crack software registrations by going offline, etc.

Furthermore, mobile applications have to be tested on both wifi internet and mobile data, often switching between the two, as well as exploring scenarios when the internet isn’t available for a span of time between connectivity.

OS compatibility vs. browser compatibility

For web applications, cross-browser compatibility is a mandatory aspect to test. Not all browsers support the same level of functionality, though major browsers do behave similarly. Also, testing the application to validate the minimum supported browser version is important to ensure end-users are not frustrated with a broken user experience caused by an outdated/unsupported browser.

Client-Server Testing

When testing client-server communication for desktop and mobile apps, proxy server tools like Postman and Charles are usually required to validate whether the server is sending correct responses to the clients. This can help in assigning bugs to either server developer teams or client developer teams. 

For web applications, browsers come with built-in inspection tools. On any major browser, right-click and select ‘Inspect element’ to inspect network traffic, code console errors, web app security elements, etc. 

Mobility Testing

Mobile devices are designed to be used on the move which adds several additional challenges for testing as compared to web and desktop apps. Many mobile apps are location-aware, using the geo-location of the device to provide interesting capabilities to the user. Testers need to know the interesting locations and have the ability to simulate the device being in various locations. Also, mobile devices started out as telephones, and are still used as such, which adds “interrupt” testing to the mix – where the tester sees how the app responds when the phone receives a call or text.  


Desktop and web applications provide a lot of screen real estate. Generally, these applications offer a wide range of functionality, including user-role based functionality for Admin users. This increases both the scope of testing and the depth of testing. Both the UI and UX are designed keeping in mind that the user will have a physical keyboard and mouse to interact with the app. Similarly, the UI is designed for more activity and actions per screen. 

Application updates

Bottom line