Espresso is a testing framework for Android that makes it easy to write reliable user interface tests directly within the Android Studio Integrated Development Environment (IDE). It's targeted at developers who understand that automated testing is an integral part of the development lifecycle. Espresso can be used for black-box testing, but its full power is unlocked when the codebase under test is exposed and accessible at the source code level. This allows developers to use Espresso to do mobile website tests against browsers embedded in cell phones and tablets, as well as run against features in native applications. Espresso is powerful and flexible, making it a useful tool for both browser-based and native application testing. Android Studio organizes UI tests under the category name "androidTest" and business logic tests under "test". The Espresso Test Recorder allows developers to create Espresso tests by automatically recording interactions performed upon a device emulator. This feature saves significant time in test creation and allows developers to add assertions during recording sessions. After running tests, Android Studio displays pass/fail information and coverage reports within the IDE, which can be exported into HTML documents for further inspection. By mastering Espresso, developers can integrate comprehensive testing into their software development experience, find issues earlier, and make quality code that meets essential requirements.