We verify that all features and functions of the complete application work correctly according to the requirements. This includes testing login, registration, search, payments, forms, and complete user workflows.

We check how the complete system performs under different workloads and user traffic. Response time, speed, stability, scalability, and resource usage are tested to ensure smooth performance.

We verify that the application and user data are properly protected. Authentication, authorization, access control, session management, and data security are tested to identify possible security issues.

We test the application across different browsers, operating systems, devices, screen sizes, and environments to make sure it works consistently everywhere.