Top Mobile Testing Interview Questions And Answers

In the fast-evolving landscape of mobile technology, the importance of mobile app testing has become more crucial than ever. Mobile app downloads have consistently doubled every quarter since 2015, emphasizing the expanding market for mobile applications. The reliance on apps has also grown, with 86% of people spending more time on apps than on websites.

The surge in mobile device usage and app downloads has significantly heightened the risks associated with bugs and issues in mobile applications. This makes thorough testing an indispensable aspect of app development.

What is Mobile Testing?

Mobile testing is a process which involves evaluating and verifying the functionality, usability, performance, and consistency of mobile applications across a range of devices, platforms, and network conditions. It ensures that the app performs as expected on various devices, operating systems, and under different network conditions.

Why Mobile Testing is needed?

Considering the wide range of devices and OS versions that are launching on a day-to-day basis, it becomes crucial to make sure that the app is running across all platforms. Let’s have a deeper look as to why mobile testing is indispensable part of software testing today:

• Diverse Devices and Operating Systems: The variety of mobile devices and operating systems requires testing to ensure apps work seamlessly across all platforms. For instance, an app must perform equally well on different versions of iOS and Android, and on various screen sizes and resolutions.

• User Experience and Retention: With high app uninstallation rates (94% of users remove mobile applications within 30 days of installation), it's essential to ensure an app is intuitive, easy to use, and free from bugs to retain users.

  
  
  
  

• Performance Under Varying Conditions: Mobile apps need to perform under different network conditions and user loads. Testing helps identify and rectify issues related to speed, responsiveness, and resource usage.

  
  
  
  

• Market Competition and Brand Reputation: In a highly competitive market, a well-functioning app can enhance brand reputation and user loyalty. Mobile testing helps in delivering a high-quality product that stands out in the market.

Top 20 Mobile Testing Interview Questions

Now that we’ve covered the basics, let’s delve into the mobile testing interview questions and answers. Here we have covered 30 most frequently asked questions with a detailed answer and examples to help you understand better.

1) Is mobile application testing and mobile app testing the same?

"Mobile application" and "mobile app" are interchangeable terms. An app (short for "application") is a type of software designed to run on mobile devices such as smartphones and tablets. The main goal of mobile app testing is to identify any bugs or issues before the app is released to the public. This includes testing the app's functionality, usability, performance, compatibility with different devices and operating systems, and security.

2) What are the different types of mobile app testing?

Mobile app testing has become a huge domain now, with multiple types of testing branching from it. Here is a list of most common testing types:

Testing Types:

• Functional Testing: Ensures the app works as intended.

• API Testing: Ensuring the working logic behind the app that is carried over by APIs works well

• Usability Testing: Assesses the user experience and ease of use.

• Performance Testing: Checks the app’s responsiveness, speed, and stability.

• Compatibility Testing: Verifies that the app works across various devices and OS versions.

• Security Testing: Ensures the app is safe from external threats.

3) What typical difficulties do testers often encounter when testing mobile applications?

Testing mobile applications presents several unique challenges, often distinct from those encountered in traditional software testing. These challenges include:

• Diverse Operating Systems and Versions

• Device Fragmentation

• Network Variability

• Battery Consumption

• User Interface and User Experience

• Performance Testing

• Security Concerns

• Localization and Internationalization

• Integration with Device Features

• Regulatory Compliance

  
  
  
  

Each of these challenges requires a specific set of skills and tools, making mobile application testing a specialized and evolving field.

4) What distinguishes mobile testing from mobile app testing, and could you elaborate on the technical nuances that set them apart?

Mobile testing broadly encompasses assessing the functionality, performance, and usability of mobile devices, including both hardware and software aspects.

On the other hand, mobile app testing specifically focuses on scrutinizing the applications developed for mobile platforms. The key distinctions lie in their scope and objectives.

Mobile Testing: Mobile testing involves evaluating the overall functionality of mobile devices, ensuring they operate seamlessly across various scenarios. This includes testing features like call handling, network connectivity, battery life, and hardware components such as sensors and cameras. For example, validating that a mobile device smoothly switches between Wi-Fi and cellular networks without disruptions is part of mobile testing.

Mobile App Testing: Mobile app testing, on the contrary, concentrates on the individual applications designed for mobile platforms. This encompasses functional testing to ensure app features work as intended, usability testing to gauge the user experience, and performance testing to assess speed and responsiveness. An example of mobile app testing would be validating that all features within a banking application, such as fund transfers or account balance inquiries, perform accurately and efficiently.

Technical Nuances: In mobile testing, technical aspects involve examining the device's hardware capabilities and software functionalities. This may include checking compatibility with different operating systems and versions. In mobile app testing, technical nuances revolve around the intricacies of the application's code, its compatibility with various devices, and its responsiveness to different screen sizes.

For instance, in mobile testing, you might assess the GPS functionality of a device across different locations. In mobile app testing, you would scrutinize how a mapping app utilizes and accurately displays location data, ensuring a seamless user experience.

5) Throw some light on mobile testing life cycle.

The mobile testing life cycle is a systematic process that ensures the quality and effectiveness of mobile applications.

1. Requirement Analysis: Understanding the app's functionality, target audience, and platform (iOS, Android). For example, a banking app requires high security and user-friendly features.

2. Planning: Defining scope, resources, timeline, and test types (functional, usability, performance). Example: Planning to test a shopping app's load time during sales.

3. Designing Test Cases: Creating test scenarios and scripts based on requirements. For instance, testing all payment methods in an e-commerce app.

4. Environment Setup: Preparing the necessary hardware and software, like different mobile devices and OS versions. Example: Testing a game on various smartphones with different screen sizes.

5. Test Execution: Running the test cases and logging defects. Example: Checking a navigation app's accuracy in different locations.

6. Defect Reporting and Retesting: Reporting found issues and verifying fixes. E.g., a social media app's bug fix for photo upload.

7. Final Testing and Closure: Ensuring all requirements are met and preparing test closure reports. Example: Verifying a music app's final version before launch.

   
   
   
   

6) Is there a way to check the CPU usage on mobile devices?

Yes, there are several ways to check CPU usage on mobile devices. Here are a few methods:

1. Built-in Settings: Many mobile devices have built-in settings that allow you to monitor CPU usage.

2. Third-Party Apps: Numerous third-party apps are available on both the Google Play Store (for Android) and the Apple App Store (for iOS) that allow you to monitor CPU usage. Examples include CPU-Z, GSam Battery Monitor, or 3C System Tuner for Android, and System Status, Lirum Device Info Lite, or CPU DasherX for iOS.

3. ADB Commands (Android): For advanced users with access to the Android Debug Bridge (ADB), you can use ADB commands to check CPU usage.

4. Xcode Instruments (iOS): For iOS app developers using Xcode, the Instruments tool provides a way to profile and monitor various aspects of an app's performance, including CPU usage. This is particularly useful for developers during the app development and optimization process.

   
   
   
   

7) Could you list some tools used for tracking bugs that are effective for testing on mobile devices?

Some of the bug tracking tools are:

1. JIRA: A widely-used tool that offers comprehensive issue and project tracking. It is highly customizable and integrates well with other development tools.

2. Bugzilla: An open-source tool known for its simplicity and effectiveness in bug tracking. It's suitable for various development environments, including mobile.

3. MantisBT: Another open-source option, MantisBT is user-friendly and offers essential features for tracking bugs in mobile development projects.

4. TestRail: This tool provides test case management along with bug tracking, making it a good choice for mobile testing where test cases are frequently revised.

5. TestFairy: Specifically designed for mobile app testing, TestFairy offers video recording of test sessions, which can be invaluable for understanding exactly what happened before a bug occurred.

   
   
   
   

8) Why API testing is a crucial part of mobile app testing?

API testing is crucial in mobile app testing because it ensures the app interacts correctly with backend services, maintains high performance and security standards, provides a consistent user experience across different devices, and facilitates efficient integration with third-party services. It also helps in identifying issues early, reducing the overall development cost and time.

9) Name some of the critical API errors that you can encounter while performing mobile app API testing.

In mobile app API testing, you might encounter several critical API errors, each indicating different issues in the communication between the app and its backend services. Some of these errors include:

• 400 Bad Request

• 401 Unauthorized

• 403 Forbidden

• 404 Not Found

• 500 Internal Server Error

• 502 Bad Gateway

• 503 Service Unavailable

• Timeout Errors

10) Name a few API testing tools that can be used for mobile app api testing.

API testing is an integral part of the mobile app development process, ensuring that the application interfaces function correctly, securely, and as expected. Here are some effective API testing tools:

1. HyperTest: HyperTest is an automated API testing tool that is designed to be highly efficient and easy to use. It offers rapid test creation and execution, making it an excellent choice for agile development environments.

2. Postman: Widely popular for its user-friendly interface, Postman allows testers to create, share, test, and document APIs. It supports various types of HTTP requests and can handle different data formats.

3. SoapUI: This tool is excellent for testing SOAP and REST APIs. SoapUI allows for both functional and non-functional testing and supports extensive test automation.

   
   

4. JMeter: Primarily used for performance testing, JMeter can also be used for API testing. It is open-source and can simulate heavy loads on a server to test its strength and analyze overall performance under different conditions.

5. Katalon Studio: A versatile testing tool that supports both UI and API testing for mobile apps. It offers a comprehensive set of features for API testing, including test case management, test execution, and reporting.

11) How emulators and simulators play role in mobile testing?

Emulators and simulators are crucial in mobile testing as they provide a cost-effective and efficient way to test apps across various devices and operating systems without needing physical devices. Emulators replicate the hardware and software environments of actual mobile devices, while simulators mimic the software and OS environment. They allow developers to quickly test and debug applications in different scenarios, ensuring app functionality and user experience are consistent across diverse platforms. This flexibility is essential for identifying device-specific issues early in the development cycle, thus saving time and resources.

12) What are the common bugs found while performing mobile testing?

Common bugs encountered during mobile testing include:

1. User Interface Issues: Misalignment, incorrect scaling, and inconsistent visual elements across different screen sizes.

2. Functionality Flaws: Broken links, improper handling of user input, and failures in executing certain features.

3. Performance Problems: Slow app response, excessive battery consumption, and memory leaks.

4. Compatibility Issues: Incompatibility with different OS versions, screen sizes, or device orientations.

5. Connectivity Errors: Issues in handling network changes (like switching from Wi-Fi to mobile data) and in managing data synchronization.

6. Security Vulnerabilities: Weak encryption, unauthorized data access, and privacy breaches.

13) Manual testing a mobile app or implementing automation testing. What should be implied under which scenario?

Manual testing is ideal for exploratory, usability, and ad-hoc testing, where human insight is crucial. It's best for assessing user experience and interface design. Automation testing suits repetitive, regression, and performance testing, where consistency and speed are vital. It’s efficient for large-scale test cases, frequent code changes, and long-term projects, ensuring thorough, time-efficient coverage.

14) Explain the importance of test data in manual mobile testing.

Test data is pivotal in manual mobile testing as it simulates real-world conditions, ensuring the app functions correctly under various scenarios. Good test data helps in uncovering hidden bugs by mimicking diverse user inputs and behaviors. It also verifies how the app handles different data formats and edge cases. Accurate test data is essential for thoroughly evaluating the app’s performance, functionality, and security, thus playing a key role in delivering a reliable and user-friendly mobile application.

15) How do you perform performance testing on mobile applications manually?

To perform manual performance testing on mobile applications, start by defining key performance indicators like load time, response time, and memory usage. Test the app under various network conditions (3G, 4G, Wi-Fi) and on different devices to assess its behavior. Monitor battery usage, app stability, and how it handles large data or multiple tasks simultaneously. Pay attention to how the app performs during prolonged usage to identify memory leaks or overheating issues. Document all findings meticulously for analysis, aiding in optimizing the app's performance for an enhanced user experience.

16) Explain the advantages of mobile automation testing over manual testing.

1. Efficiency: Automated tests run faster and can be executed repeatedly, saving time in long-term projects.

2. Consistency: Automation ensures tests are performed identically each time, eliminating human error and variability.

3. Scalability: Automated tests can easily handle large volumes of test cases, making them ideal for complex apps.

4. Coverage: Automation can test more scenarios and use cases, improving the overall test coverage.

5. Cost-Effectiveness: Although initially costly, it reduces long-term testing costs through repeated use.

   
   

17) Explain the concept of continuous integration in mobile automation testing.

Continuous integration (CI) in mobile automation testing involves integrating code changes into a shared repository frequently, ideally several times a day.

Each integration is automatically tested, often using an automated build and test process. This practice allows teams to detect issues early, reducing the time and effort required for integration. CI maintains the health of the software, ensuring that new changes don’t break functionality, thus facilitating faster, more reliable development cycles in mobile app development.

18) How do you test mobile applications for different screen sizes and resolutions?

Testing mobile applications for different screen sizes and resolutions involves using a combination of real devices and emulators/simulators.

Start by identifying the most popular devices and screen resolutions among your target audience. Test the app on these specific devices to ensure compatibility and proper display. Utilize emulators and simulators to cover a wider range of devices and resolutions, particularly for those not physically available. Focus on UI elements, layout responsiveness, and functionality to ensure a consistent and optimal user experience across all screen sizes and resolutions.

19) What are the common mobile app api testing challenges faced by the developers?

1. Device Diversity: Testing across a multitude of devices, OS versions, and screen sizes.

2. Network Variability: Ensuring consistent performance across different network conditions and speeds.

3. Security Concerns: Addressing vulnerabilities and ensuring data protection and privacy.

4. Parameter Combinations: Managing extensive combinations of input parameters.

5. Session Management: Testing APIs for proper session handling, especially in multi-user environments.

6. Error Handling: Ensuring APIs respond gracefully to unexpected inputs and conditions.

7. Integration Complexity: Testing APIs in the context of their interaction with other systems and services.

   
   

20) How do you perform localization testing for mobile applications?

Localization testing for mobile applications involves checking the app's adaptability to different languages and regional settings. This includes verifying translations, layout appropriateness for text expansion or contraction, and ensuring cultural appropriateness of content and graphics. It also involves testing for correct functionality under various regional settings and formats, such as date, time, currency, and number formats, to ensure a seamless user experience in each specific locale.

21) What is mobile application security testing?

Mobile application security testing is the process of evaluating and ensuring the security aspects of a mobile app. It involves identifying and mitigating security vulnerabilities to protect against threats like unauthorized access, data leakage, and malicious attacks.

This testing assesses various elements, including data encryption, authentication, authorization, session management, and network security. It aims to safeguard sensitive user data and ensure compliance with relevant security standards, thereby enhancing the overall trustworthiness and reliability of the mobile application in handling user data and interactions.

22) What is a Robolectric testing framework?

Robolectric is an open-source Android unit testing framework that allows developers to write and run Android tests directly within the Java Virtual Machine (JVM).

This approach eliminates the need for deploying the app or tests to an Android device or emulator, facilitating faster and more efficient test execution. Robolectric simulates the Android SDK, including activities, services, and intents, enabling comprehensive testing of Android applications in a desktop development environment.

We’ve completed our blog with 20 most-frequently asked questions, learn this modern approach now to gain insights on how to perform Mobile App API Testing in this agile development phase.

Schedule a demo with HyperTest today to sort your Mobile App API Testing!