A Guide to Usability Testing for Mobile Apps

In 2022, 3.8 trillion hours were spent using mobile apps, with Android and iOS app revenue anticipated to hit over $935 billion. This rise in mobile app use requires app developers to do all they can to get and keep users in a competitive market. For example, if customers have to jump through hoops to buy basic items in an e-commerce app, why would they return?

In usability testing, representative users help teams evaluate the quality of their mobile apps as part of the app testing and development process. Relying on actual users outside your team gives you a much better idea of how user-friendly your app’s user interface (UI) is for its intended audience. 

This guide explains why usability testing is important for mobile apps and the steps you should take when conducting this type of testing. 

The purpose of usability testing is to validate that actual users of your app will have a high-quality experience with minimal confusion or frustration.

Usability testing is usually introduced after the mobile app has been built by developers, thoroughly vetted in functional testing, and all the identified bugs have been fixed. It’s usually conducted before designing new features, to ensure that design teams know what your customers want or to pinpoint new opportunities for later iterations.

Usability testing helps you:

As with all quality assurance (QA) methodologies, you must follow a standardized process for consistent and reliable results. Let’s go over the seven steps you should follow with usability testing.

In functional test methodologies, such as end-to-end testing and system testing, objectives are based on verifying that key features work as intended. Usability testing differs by assuming functionality already works; instead, it focuses on evaluating user interaction with the app.

It's important to identify test objectives after functional tests have concluded, as well as before beginning any new product designs.

While determining your objectives, be sure to include features that may pose a usability risk for your user base. For instance, if you notice a drop-off in user registrations, you may want to look into why that’s the case. Does your registration form take too long to complete? Is it too complex for the average user? 

Next, define research goals and list questions you want participants to answer. A testing checklist could be written as follows:

Usability testing tasks should be realistic activities that participants can complete to determine what works on your mobile app and what doesn't. It's best to write tasks as one-sentence commands to avoid confusion. For example, "Buy a video game from the electronics page," or "Navigate to x page."

However, it's also important to let users perform tasks in the same way they would engage with the mobile interface in real life. If you can avoid making tasks feel like a clinical trial, you'll get a much better grasp of how your target users interact daily with mobile apps.

Give testers the freedom to interact with your mobile app. Instead of forcing testers to use a specific feature, let them choose how they complete tasks. For example, in addition to instructions, also craft test scenarios like this:

You're going to your brother's birthday party. For his gift, you decide to buy Super Mario Kart for PlayStation 2. Go to the GameStop mobile app and see if you can buy it there.

The tasks for this test scenario could be constructed as:

Finding and recruiting testers for your mobile app is important, but it can be a time-consuming process. Luckily there are tools that can help. Apple and Google both offer native beta app stores that can help you find beta testers. Sauce Mobile Beta Testing can also help streamline the distribution and management of your iOS and Android apps and improve feedback cycles with data from real users.

Unless your app is designed to be used in specific locations (like an in-person grocery shopping app), there's no need to build a lab for usability testing. This is because most mobile app use cases are independent of the location in which they're used.

Using a cloud-based mobile testing provider like Sauce Labs is a more convenient and cost-effective solution. You want to choose a solution that has everything you need for effective usability testing in one platform with the ability to integrate with any tools you're already using for CI, accessibility, collaboration, etc.

When running the test itself, give participants their tasks and then don't interfere as they complete them. Interfering defeats the purpose of usability testing, as your goal is to observe natural behavior with your app. 

Also, be mindful of how long your usability test runs are. A good standard is that usability tests should take fifteen minutes to an hour, depending on the complexity of the tasks to be performed.

After concluding a test run, it’s time to aggregate data and identify actions. Usability test reports should include a summary, methodology, test results, and recommendations so that those not involved with the tests can interpret the results.

The summary should provide an accurate overview of the usability test itself. Cover information such as: 

Test results should include metrics such as the number of errors, task time, and completion rate to determine mobile app quality. Also include the average time spent per task and completion rates per task, as those data points can also provide insight into the strengths and weaknesses of your mobile app.

Always conclude with recommendations. No usability test is useful unless action is taken. Recommendations can range from completely redesigning key features to making minor changes to the user interface. 

Prioritize issues and recommendations using severity. For example, if you've discovered your mobile app navigation is slightly confusing and it also takes ten minutes to fill out a user registration form, which is more important?

Whether you're part of a mobile app startup or a multinational corporation, usability testing can help you evaluate how user-friendly your mobile app is. Following a few specific steps, you can be sure to get useful results from your usability testing.