Mastering Mobile App Testing with Automated Screenshot Testing

Mobile devices have become a go-to solution for most businesses these days. From managing finances to grocery shopping or managing operations, the mobile is a handy solution to all the operations.

Therefore, it has become more important than ever to create applications that can offer flawless output and the desired user experience. However, mobile application development has become more complicated with growing functionalities and end-user demands.

According to reports, one in four mobile applications contains at least one high-risk security flaw. Besides, 50% of apps that have five to ten million downloads include some security flaws.

Here comes the roles of mobile testing and advanced test automation practices like automated screenshot testing.

Actually, visual and test automation go hand in hand when it comes to the mobile app development lifecycle. While functional tests ensure the app performs as expected, visual tests focus on user experience, ensuring the UI elements are correctly rendered and positioned.

Therefore, visual testing is one of the most significant components of comprehensive mobile app testing.

This blog will delve into the world of Automated Screenshot Testing, emphasizing its vital role in both visual and test automation and shedding light on its advantages, best practices, test setup, tools, and more.

Let's begin!

Mobile App Automation With Screenshot Testing

Automated Screenshot Testing is a game-changer in mobile app testing. But before we jump to the details surrounding automated screenshot testing, it is necessary to understand the term.

Automated screenshot testing as a test approach enables developers and QA teams to capture screenshots of different screens within the app automatically. These screenshots further serve as visual checkpoints, allowing for quick identification of any deviations from the expected UI.

Wondering how it incorporates the UI Testing Component?

Automated Screenshot Testing is not just about capturing screenshots but also involves UI testing. By comparing the screenshots against predefined baseline images, the technique ensures that the app's UI remains consistent across various devices and operating systems.

In other words, screenshot testing is instrumental in identifying UI regressions and preventing visual glitches.

Advantages Of Screenshot Testing In Mobile Automation

One of the most significant reasons automated screenshot testing is implemented is its potential to enable QA teams to identify any unintended changes in the UI swiftly. Besides, it helps catch regressions early in the development cycle, preventing them from reaching the end-users.

Some of the benefits that testers could enjoy with automated screenshot testing could be listed as:

• Cross-Platform Compatibility Assurance

  With the multitude of devices and platforms available, ensuring consistent UI across them can be challenging. Screenshot testing provides a reliable way to verify cross-platform compatibility, ensuring a seamless user experience.

• Efficient Bug Detection

  Screenshot testing complements functional testing by visually highlighting any anomalies. The process makes bug detection more efficient and precise, reducing the time and effort required for debugging.

• Improved Collaboration

  The visual nature of screenshot testing facilitates more transparent communication between developers, designers, and QA teams. Also, it provides a tangible reference point for discussing UI-related issues complementing the test process and development.

• Enhanced User Satisfaction

  When testers need to attain a polished and visually appealing UI to meet user satisfaction goals, automated screenshot testing can be harnessed to boost app retention rates.

Best Practices For Automated Screenshot Testing

While investing in automated screenshot testing is a consuming task for most test teams, implementing the same in the QA workflow could deliver the necessary speed and accuracy required to create mobile applications with rich UI and visual flawlessness.

1. Keep Tests Atomic and Isolated

   Each test case should focus on a specific functionality or UI component. It helps in confirming a clean and organized test suite.

2. Use Test Data Generation

   Automate the process of generating test data to ensure consistent and repeatable results. It helps in avoiding false positives in the visual tests.

3. Leverage Headless Browsers

   Headless browsers allow you to run tests in a simulated environment without a graphical user interface. It significantly speeds up the testing process and saves the consumption of system resources.

4. Regularly Review and Update Tests

   As your application evolves, it's important to review and update your test cases to reflect any changes in the UI or functionality. Screenshot testing helps to fasten the test process, cutting off the latencies.

Setting Up Automated Screenshot Testing

Step 1: Choose a Testing Framework

There are several popular testing frameworks available for automated screenshot testing. Some of the widely used ones include:

• Puppeteer: A Node.js library developed by Google that provides a high-level API for headless Chrome.
• Selenium: A versatile browser automation framework that supports multiple programming languages.
• Cypress: A JavaScript end-to-end testing framework that also provides screenshot-capturing capabilities.

It is important to choose a framework that aligns with a project's specific requirements and the selection of programming languages.

Step 2: Write Test Cases

Once you've selected a testing framework, it's time to start writing test cases. These test cases should focus on the critical paths and UI components of your application. For example, capture screenshots of the homepage, product pages, and all other interactive elements.

Step 3: Capture Screenshots

Using the chosen testing framework, you can programmatically navigate the application and capture screenshots at specific points in the defined test cases. Make sure to organize all the screenshots in a structured way, allowing quick comparison between different versions.

Step 4: Implement Visual Regression Testing

To perform visual regression testing, you'll need a tool that can compare screenshots and highlight any differences. There are specialized tools available, like Applitools and Percy, that integrate seamlessly with testing frameworks. These tools provide powerful features such as pixel-by-pixel comparison, image diffing, and visual reporting. Besides, one can even switch to advanced AI-driven test automation tools like BugBot to meet their regression goals through visual testing.

Step 5: Set Up Continuous Integration

Integrating automated screenshot testing into your continuous integration (CI) pipeline ensures that your visual tests are executed automatically whenever there's a code change. It helps to catch any visual regressions early in the development process, reducing the likelihood of shipping a flawed user interface.

Screenshot Testing Using Selenium

When it comes to Automated Screenshot Testing, one name stands out: Selenium.

Selenium, as an open-source testing framework, is renowned for its versatility and robust capabilities. Besides, Selenium's WebDriver API enables seamless interaction with web elements, making it an ideal choice for capturing screenshots during automated tests.

Unique Features of Selenium for Screenshot Testing

1. Cross-Browser Compatibility

Selenium supports various browsers, ensuring screenshots are captured consistently across different platforms.

2. Flexible Language Support

Selenium can be used with diverse programming languages, like Java, Python, C#, and more, offering flexibility to development teams.

3. Integration with Testing Frameworks

Selenium seamlessly integrates with popular testing frameworks like JUnit and TestNG, streamlining the automation process.

4. Extensive Community Support

The vast community around Selenium provides access to a wealth of resources, making it easier to troubleshoot and find solutions to testing challenges.

Conclusion

In conclusion, automated screenshot testing is a powerful technique for ensuring the visual consistency of your web applications across different browsers and devices. Also, implementing the practice in the development workflow could complement catching visual regressions early, leading to a smooth user experience and higher customer satisfaction.

Besides, it is important to remember that gaining maximum effectiveness demands choosing the right testing framework, writing effective test cases, and leveraging visual regression testing tools precisely.

After all, it is only the right approach and practice that turns out to be an invaluable asset in your toolkit for delivering high-quality web applications, especially when you are deploying advanced practices like automated screenshot testing.

Good Luck!