Mobile Regression Testing

Engineering leaders tasked with improving a team's mobile development flow should know about mobile regression testing. This comprehensive guide will teach you everything you need to know about mobile regression testing. This article will go over its definition, benefits, tools, pros and cons, and specific considerations.

We'll start by defining mobile regression testing and discussing its benefits and downsides. Then we'll discuss the different types of regression tests, and when to use each one. We'll also go over the tools you need to get started, including some common approaches and designs. Finally, we'll discuss when to use regression testing. By the end of this guide, you'll have the knowledge to make informed decisions for your team.

Let's get started!

What Is Mobile Regression Testing?

Mobile regression testing is a type of testing used to ensure that changes made to a mobile application don't break existing functionality. It's typically performed after each new release or change to the app. The changes can be small, like fixing a bug, or large, like adding a new feature. Either way, mobile regression tests are essential in ensuring that the system still works as intended. While new feature testing focuses on verifying the functionality of new code, mobile regression testing seeks to uncover new software bugs in existing functionality.

In other words, mobile regression testing is simply regression testing that is specific to mobile apps. It can include testing for UI changes, new features, and performance issues.

Regression tests can be manual or automated. Automated regression tests run using a tool that can simulate a user's interactions with the app, such as opening and closing it, entering data, and so on. The tool repeats tests after each change to the app to ensure that the changes have not broken any existing functionality. We'll go through different tools for mobile regression in more depth later in the guide.

Note that regression tests are not the same as unit tests. Unit tests test individual components in isolation, while regression tests test the entire system to see how well it works as a whole.

Benefits of Mobile Regression Testing

There are many benefits to mobile regression testing. We'll discuss them below.

Reduced Risk of Breaking Existing Functionality

Firstly, it helps to ensure that changes made to the codebase don't break existing functionality. This is an essential component to mobile development, where there are often many different moving parts that need to work together. Secondly, mobile regression tests can help identify performance issues that may not appear during unit testing. For example, a change that improves the performance of one part of the code may unintentionally degrade the performance of another part.

Increased Confidence in New Releases

Mobile regression tests can help catch various types of issues before they cause problems for users. This saves time and frustration, and it also helps to ensure that the codebase is always in a state that is ready for release.

Improved Quality of the Mobile Application

Regression tests can help improve the codebase's quality over time. By catching issues early, developers can often fix them before they become hard-to-find bugs. Additionally, regression testing can help to ensure that new features are added more easily and with less time wasted on troubleshooting.

Greater Efficiency in Development

Finally, mobile regression tests can save considerable time in the long run because they can help to catch issues early in the development process. Additionally, you can run regression tests quickly and easily, and automation can help you save time and maintenance effort.

Downsides of Mobile Regression Testing

There are also some potential downsides, including that mobile regression testing:

Needs test cases - To perform regression testing, you first need to create test cases. That can be time consuming, and it might require expertise.
Affects time management - Regression testing can be time consuming, as noted above, particularly if the mobile application has many features.
Requires additional testing - When any change is made to the mobile application, test cases need to be re-run. It can be time-intensive, and it may not be necessary if only a small change was made.
Needs additional resources - Mobile regression testing may require additional resources such as dedicated testers or test servers to execute automated testing tools. It can be expensive as well.
Requires training - If you plan on performing mobile regression testing, training your testers is crucial. They should be familiar with the mobile application and the different tests they can perform. Additionally, they should know how to interpret test results and take appropriate action if an error is found.

Types of Mobile Regression Tests

Several different types of mobile regression tests exist. We'll list the most common ones listed below.

UI Tests

UI tests check to see how the UI of the app looks and feels after a change has been made. This includes things like checking for visual glitches, verifying that text is aligned correctly, and making sure that buttons work as intended.

Functionality Tests

Functionality tests check to see if the app still works as intended after a change has been made. This includes things like verifying that the app can still connect to the backend, that data is processed correctly, and that user input is handled correctly.

Performance Tests

Performance tests check to see if the app is still performant after a change has been made. This includes checking for memory leaks, verifying that the app can still handle large amounts of data, and ensuring that the UI is responsive.

Compatibility Tests

Compatibility tests check to see if the app is still compatible with the devices and operating systems it needs to support. This includes checking for crashes on older devices, verifying that the app still works with the latest version of iOS/Android, and making sure that new features don't break existing functionality.

Designing Mobile Regression Tests

When designing mobile regression tests, you should keep a few things in mind:

Test all relevant functionalities: The test cases should be comprehensive, ensuring that the test cases cover all relevant functionality. This should include both new and existing functionality.
Isolate the changes: You should always isolate the changes to fewer components. This will make it easier to design and execute mobile regression tests.
Prioritize test cases: You should prioritize your test cases based on the risks associated with the changes made in the release.
Document the test cases well: The documentation should include what to test, how to run the tests, and the expected results.
Ensure tests are simple to perform: The tests should be simple to execute so you can complete them quickly and easily.

Approaches to Mobile Regression Testing

Two main approaches to mobile regression testing exist: manual testing and automated testing.

Manual Testing

You can perform mobile regression tests manually by using the built-in tools in the iOS Simulator and Android Emulator, or by using physical devices. In this style of testing, a human tester manually executes test cases and compares the results to the expected outcomes. This approach may take more time, but it has the advantage of catching all types of errors, including ones a script or automation might not catch.

Automated Testing

With automated testing, a software tool executes the test cases. There are several different ways to perform automated mobile regression tests. The most common is to use a tool like Appium, which is an open-source framework for automated testing of native, hybrid, and mobile web apps. Another popular choice is to use a cloud-based testing service like Sauce Labs. These services provide a convenient way to run regression tests on a large number of devices without needing to set up and maintain a physical device lab. These tools automate the execution of test cases and compare the results to expected outcomes. They can save time and effort, and improve the accuracy of mobile regression testing. But they also have the disadvantage of only being able to catch certain types of errors.

There are a few potential downsides to using Appium and Sauce Labs. Firstly, both tools can be expensive to use, particularly if you need to run tests on a large number of devices. Secondly, both tools can be complex to set up and use, which can lead to a steep learning curve. If you're looking for a more effective, affordable, and easy-to-use option for mobile regression testing, Waldo is an excellent resource. It can be used to test native, hybrid, and web-based mobile apps on real devices. It offers an intuitive interface and requires no coding skills. Waldo also provides comprehensive reports that can identify potential issues and bugs.

Check out Waldo and start a free trial to learn more.

When to Perform Mobile Regression Tests

There is no hard and fast rule for when to perform mobile regression tests. However, there are a few general guidelines you can follow. Firstly, it's a good idea to perform regression tests after any major changes to the codebase. This can include adding new features, fixing bugs, and refactoring code. Secondly, it's also a good idea to perform regression tests before releasing a new version of the app. This helps ensure that the new version is stable and doesn't introduce any new regressions. Finally, it's also a good idea to perform regression tests regularly, even in the absence of major changes. This helps to keep the codebase healthy. It also catches regressions early, before they have a chance to cause problems for users.

Conclusion

Mobile regression testing helps identify bugs and regressions in mobile apps. It's generally performed after significant changes to the codebase, before releasing new versions of the app, and on a regular basis.

This post was written by Peter Morlion. Peter is a passionate programmer that helps people and companies improve the quality of their code, especially in legacy codebases. He firmly believes that industry best practices are invaluable when working towards this goal, and his specialties include TDD, DI, and SOLID principles.