Mobitest by Akamai is a free mobile performance testing tool to give you a deeper understanding of how to improve your mobile website’s web performance. Mobitest can provide you with a video of your website loading, the HAR file of your runs, the average loadtime, and the average size of your mobile website. Mobitest is built off of the webpagetest.org framework and leverages real devices to extract the data.
Mobitest was open-sourced in march 2012.
Other web testing tools for mobile devices are MobileOK and MobiReady.