Selenium
Selenium is a popular open-source automation framework primarily used for web application testing. It provides a suite of tools and libraries that enable developers and testers to automate web browser interactions, such as clicking buttons, entering text, and verifying page content. Selenium is widely adopted due to its flexibility, cross-browser compatibility, and community support.

Pros

Open-Source: Selenium is freely available, making it accessible to anyone.

Cross-Browser Compatibility: It supports various web browsers, including Chrome, Firefox, Edge, Safari, and Internet Explorer.

Language Independence: Selenium can be used with multiple programming languages like Java, Python, C#, Ruby, and JavaScript.

Community Support: A large and active community provides extensive documentation, tutorials, and forums.

Extensibility: Selenium can be extended with plugins and libraries to support additional features and testing scenarios.

Integration with Other Tools: It can be integrated with other tools like TestNG, JUnit, and CI/CD pipelines for comprehensive testing.

Cons

Initial Setup: Setting up Appium can be time-consuming, especially for beginners. 

Device Management: Managing physical or virtual devices for testing can be challenging. 

Performance Overhead: Appium can introduce some performance overhead, especially when testing complex apps. 

Browser-Specific Quirks: There might be occasional differences in behavior across browsers within mobile apps. 

Benefits

Automated Mobile Testing: Appium enables you to automate testing of mobile apps, saving time and effort.

Cross-Platform Testing: Ensures that your mobile apps work consistently across iOS and Android.

Integration with Other Tools: Appium can be integrated with your existing testing infrastructure for a comprehensive solution.

Community-Driven Development: The active community ensures that Appium stays up-to-date and receives regular improvements.