Mobile App Testing – A Complete Guide

Gone are the days when people used to turn on their PC/laptop for watching online content, surfing the internet, sending emails, or even conducting online meetings. Nowadays, mobility solutions have taken over the market where handheld devices serve most of the everyday functions. Considering that mobile apps have become a very crucial element of our daily lives, it becomes very crucial for the mobile app developers to deliver faultless mobile apps. In this article, I’ll take you through the process of mobile app testing, but first, let’s know the types of mobile app testing, its significance, and the strategies that should be followed while testing a mobile app.

Mobile App Testing – Significance

Testing mobile apps is more challenging than testing web or desktop applications because of three reasons. First, there is a larger variety of mobile devices that exist in comparison to web applications. This is because of the  different screen aspect ratios and hardware configurations like processing speed and available memory that are apparent on a mobile. Second, different mobile operating systems are being used by different mobile manufacturers like Android and iOS. Third, the operating system versions keep upgrading and thus it becomes crucial to test if the mobile app is compatible with the newer OS version.

Like every other application, mobile app testing is also very important as for certain apps, the clientele is millions and hence, an app with bugs is never appreciated. Launching an app with faults results in brand image damage and monetary losses or sometimes, it can lead to legal issues as well.

Types of Mobile App Testing

To address all the potential issues that can occur after launching the mobile app, the following types of tests are performed for almost every mobile app.

• Usability testing – Mobile app usability testing makes sure that the app user interface and experience is easy to understand and use which improves user satisfaction.
• Compatibility testing – A mobile app has to be compatible with multiple mobile devices, operating systems, browsers, screen sizes. Compatibility testing makes sure that the app runs perfectly on different environments, specified in the requirement document.
• User Interface and Experience testing – UI/UX testing is for making the menu, buttons, navigation flow, and many other UI/UX elements at par with the user expectations.
• Low-level resource testing – issues related to device memory usage, auto-deletion of cache memory and temp files, and local database management comes under low-level resource testing.
• Performance testing – Testing mobile app performance for the required mobile networks and making sure that the app doesn’t crash in several scenarios. Also, analysing the device battery consumption while using the app and monitoring the mobile API usage bottlenecks.
• Operational testing – Testing the backup and recovery plan in case the battery goes down or ensuring no data loss while updating the mobile app from app stores.
• Installation testing – It includes validating the app by installing and uninstalling it on several different mobile devices.
• Security testing – Testing the application to ensure that the user data is safe from phishing or any other cyber attacks.

Mobile App Testing Process Step 1. Outlining the process

Before the mobile app tester decides the use cases which they’ll either test automatically or manually, it is advisable to first outline the list of all the use cases they’ll be testing. They should create a test plan for the mobile app which will consist of all the use cases and scenarios they want to test. The goal behind outlining is to describe the desired tests and their results. A good place to start when creating the test plan, is to study the Product Requirement Document.

Step 2. Select the type of test you want to run

Choosing whether the tests will be automated or manual is the second step in the process of mobile testing. Although, it isn’t easy to choose which testing method will be best for your particular use case, hence, I’ve created a list to help you decide whether you should test manually or automated.

Use automated testing when:

• You frequently run a particular type of use cases. It is reasonable to automate the routine tests that you run on a regular basis to check the basic functionality of the mobile app. In the long run, it will pay off the time spent on creating an automated test for such repetitive tasks, as it will save you time and eliminate potential errors that are caused by repetition. 
• Your test has a predictable outcome. For every conditional testing, test automation is a perfect pick. For example, conditions like ‘if the user taps a button, a new window will open’ has a clearly defined outcome, and there are very little efforts required from the tester’s side to consistently monitor the outcome.
• You’re testing the app’s compatibility with an array of hardware devices. You will be required to do a lot of testing if you want your app to run smoothly on a variety of mobile devices. Manually conducting all of these tests is challenging. Hence, it is better to use automated tests for device fragmentation.

Step 3. Prepare test cases for different functionalities

When you’ve decided the mobile application testing methodology that you’ll be using for your tests, you should define the cases you want to write tests for. At this stage, you can consider the following two approaches:

1. Requirement-based testing where the performance and reliability of required app features is tested.
2. Business case-based testing the assessment of the app is done based on the business perspective.

The test cases for mobile app assessment depends on the type of test you want to perform. All the mobile app tests are broadly divided into two categories – functional and non-functional.

The functional tests include:

• Unit testing
• System testing
• Integration testing
• UI/UX testing
• Regression testing
• Acceptance or beta testing

Non-functional tests include:

• Stress testing
• Security testing
• Performance testing
• Volume testing
• Reliability testing
• Load testing
• Localisation testing
• Compliance testing

Till the end of this step of mobile app testing, you should have a list of tests that you want to run for the app. When you have the list, it’s time to move to the next step – the actual mobile app testing process.

Step 4. Manual Testing

Although many developers and testers favour automated testing over manual,with an Agile testing framework, it is always recommended to utilise the combination of automated and manual testing.

If the mobile app developer kicks off a testing sprint as per the test plan, it is good for him to begin with exploratory manual testing. Manual testing doesn’t require heavy initial investment in terms of time and money, which is another reason to adopt manual testing at the early stages.

With manual testing, you should always keep consistent logs of your testing sessions in a document or excel sheet. If you are planning to engage a few testers simultaneously on the testing process, you can consider running simultaneous manual tests which will save you time for the later stages.

Step 5. Automated Testing

After conducting a few manual testing sessions and detecting the pattern of outcomes, you can consider automating most of the test cases based on their predictability and frequency.

For your understanding, tests such as load testing, performance testing, spike testing, stress testing, are very commonly tested with automation. 

With test automation, the most crucial thing is the selection of the right tool. The market is filled with many test automation tools, but in order to find the most suitable one for your mobile app testing, here I will mention a few points:

• Consider the tool that supports various platforms: Your app can be built for iOS or Android or both. You will be required to run tests for different programming languages (.NET, C#, etc.) to test your app. You would not want your testing tool to restrain you with a couple of programming languages. Thus, you should select the mobile app testing tool that allows you to test on a wide range of platforms, even if you are not required to test on those platforms at the moment.
• The tool that has rich features: Features like recording tests and playback will make mobile app testing easy and convenient for the testers. Also, do remember to manually write automated tests.
• Reusable and change-resistant: Tool that allows your testers to run reusable and easy-to-maintain tests should be preferred by you, as they will save you a lot of time running new tests in the future.

Step 6. Usability and Beta Testing

A common misconception among testers is that the beta testing can replace usability testing as both of them focus on similar issues. Still, it is worth performing both types of tests.

You can begin with a usability testing session sprint. During the designing phase, it is always better to have the end-user point of view. The usability tester will showcase the potential features and narrow down the list of features which were perfectly received by the end-users.

Beta testing is helpful in the product building strategy where you build the app from start to end and then you want to get the end-user’s feedback on the entire system before you roll out the application to the app stores. Similar to the usability testing, the beta testing enables testers to understand the features which are very necessary for the users.

Hence, both usability and beta testing are worth paying attention to. However, there is a difference between both the testing methods. In usability testing, the tester knows if a feature works or not whereas with beta testing, the tester gets a clear understanding of whether the users will be using a particular app feature frequently. A popular method for iOS beta testing is Testflight.

Step 7. Performance Mobile App Testing

When you’ve completed the usability and beta testing for every app feature, now is the time to test the performance of the entire system. This is where mobile app performance testing comes into play. The test helps in evaluating the speed, stability, and scalability of the app under high amounts of traffic.

Before you even start testing the app performance, always determine the capabilities the app is supposed to offer. You should know the intended use cases for the app as well as the favorable situations under which the system will sustain.

To make sure the success of performance testing, you should set realistic expectations and benchmark scores. While keeping away from developer’s perspective, try to look from the end-user’s perspective to ensure the efficiency of performance testing.

Step 8. Security and Compliance App Testing

Mobile apps have to be compliant to a lot of data security and standards. Depending on the industry the app is catering to, the compliance and government regulations differ. Here are some common security guidelines for mobile apps:

PCI DSS – These data security requirements are for mobile apps that allow users to make payments.

HIPAA – These security compliances are for mobile apps that are targeted to the healthcare sector. It helps in securing the patient’s personal as well as medical data.

FFIEC – these guidelines are for banking and financial institutions. It requires the banking and financial institutions to install appropriate security measures to secure sensitive financial data.