Web usability testing and research presents challenges for accurate data collection. An instrumented browser solution, Uzilla, is compared with existing solutions, and its contributions to usability testing practice are noted. Uzilla implements a client-server architecture based on the open source Mozilla browser. Instrumentation of the browser facilitates the evaluation of Web sites and applications inside and outside of the laboratory. An integrated data collection and analysis server application decreases the effort required to understand test results and facilitates iterative testing
