Network Transition testing focuses on verifying the app's performance and behavior when transitioning between different network conditions, such as moving from WiFi to 4G or experiencing signal drops. It ensures the app remains stable and functional during such changes.

Manual Testing is primarily executed without the intervention of any testing tools. In manual testing, testers execute test cases without using any automation tools. They follow the test steps, input the defined set of data, and compare the actual results with the expected ones, relying solely on human efforts.

Contract Acceptance Testing is performed to validate that the software developed aligns with the requirements specified in the contract between the client and the vendor. This ensures that client expectations and contractual obligations are met.

A bug that was previously fixed but reappears in later phases is typically assigned the status "Reopened." This indicates that the bug was once addressed but has resurfaced, requiring additional attention and potentially a more thorough fix.

While traditional scripted testing is characterized by predefined test cases and steps which are created before test execution, exploratory testing is distinguished by the design and execution of tests in real-time. Testers engage in Exploratory Testing by actively navigating the application and designing tests on the fly based on their observations and insights.

The Page Object Model (POM) is a design pattern that promotes code reusability in automation scripts. In POM, web pages or segments of them are represented as objects within test scripts. When choosing an automation tool, the tool's ability to easily implement POM and reuse code can significantly streamline test development and maintenance.

Unit Testing is the process of verifying individual units or components of a software. Since a sorting algorithm is a singular function or component, unit tests are essential to ensure that it works correctly in isolation. This ensures that the algorithm correctly sorts data under various scenarios before it's integrated with other components.

A/B Testing allows companies to compare two versions of an application (or specific features) to determine which one is more effective in engaging users. By using this method, the company can test new designs or elements to see if they address user feedback about the application being dull or non-engaging.

Integration testing focuses on combining units or components of a software and testing them as a group. It's about validating the interactions between different modules or services in a specified flow to ensure they work together as intended in the system's broader environment. Unit testing, on the other hand, checks individual components, while system testing validates the entire application.

The primary goal of test planning in the software testing lifecycle is to set the direction and scope for the testing activities. It helps in defining objectives, strategies, and the effort required to validate that the software meets its requirements and is free from critical issues.