System testing is a level of testing where the complete system is tested as a whole. Thus, it should be prioritized when the complete system is ready for testing. This level of testing comes after integration testing and focuses on evaluating the system's compliance with the specified requirements. While unit tests evaluate individual components and integration tests ensure that those components interact well, system testing verifies that the entire system meets the desired specifications and functionalities.

Connectivity testing is essential for apps that may function differently under various network conditions. In this case, the app's performance on mobile data versus Wi-Fi can be assessed under different conditions to ensure consistent user experience. Other testing types, while valuable, may not directly diagnose this specific issue.

White-box testing, also known as Structural testing, emphasizes examining the internal structures and workings of an application. This is in contrast to black-box testing which focuses solely on the software's outputs in response to certain inputs, ignoring its internal mechanisms.

A Test Environment Specialist or Test Environment Manager is primarily responsible for setting up, maintaining, and managing the test environments. This role ensures that the testing team has the necessary tools, software, and configurations to execute test cases effectively.

Jenkins is a powerful and widely-used open-source tool that provides continuous integration and continuous delivery facilities for software development. Its extensive plugin system and integrations allow it to fit seamlessly into a DevOps environment, enabling automatic code integration, testing, and deployment processes.

Cloud-based mobile application testing offers scalable testing environments, meaning you can expand or reduce resources as per your testing needs. This scalability ensures flexibility and cost-effectiveness, allowing teams to test on multiple devices and configurations without the need for physical infrastructure, unlike traditional labs. Moreover, cloud-based testing isn't bound by geographic locations, ensuring wider test coverage.

The Agile model of Software Development Life Cycle (SDLC) emphasizes continuous iterations of development and testing. Each iteration involves phases like requirements, design, coding, and testing.

Stress Testing involves assessing the system under extreme conditions beyond its specifications. In scenarios where there's an unexpected surge in users, like company-wide events, it's vital to determine if the software can sustain the stress or if it breaks, thus helping in predicting and preventing potential crashes.

Focusing on high-priority test cases ensures that the most crucial functionalities are tested, reducing the risk of critical defects. While allocating more resources can be helpful, it might not always be feasible. Skipping testing altogether is not recommended due to high risks. Parallelizing tasks could help but prioritizing guarantees the most important areas are covered.

UI (User Interface) changes in an application can often break test scripts, especially in automation. This is because automated tests might rely on specific elements, identifiers, or layouts on the interface. Ensuring scripts are resilient to these changes reduces maintenance efforts.

A positive test case is designed to test the application under positive conditions, and it is expected to pass. Such tests confirm that a feature or functionality works as intended when provided with valid input data.

Boundary Value Analysis is a software testing technique that involves testing at the boundaries between partitions. It focuses on the values that lie at the "edges" or boundaries of the allowed input and output ranges, as these values often have a higher likelihood of causing errors.