Unit testing, mock objects and web testing framework for PHP built around test cases. If you know JUnit/JMock or some of the PHPUnit clones this will need no explanation. Includes a native web browser for testing web sites directly (no JavaScript).
IST helps test teams managing complexity by adaptively selecting and prioritizing the test cases according to past test results. ISTT guides the testers through a test session with high-level test scenarios generated on the fly.
PHPCheckclipse is an Eclipse-Plugin that enables Checkstyle features for PHP developement. This means PHPCheckclipse checks your code for coding standards while you are typing.