User agent switcher

User agent switcher is a Firefox extension for customizing the user agent of the browser developed and maintained by Chris Pederick. Users can impersonate their browser's user agent string either from the predefined set of values or defining one on their own. Many web applications refers the user agent string value to determine the user's browser, operating system and the device from which the web page is accessed. By impersonating this value, user might be able to break it.