I have been doing a lot of mobile development lately. One tool I have found to be irreplaceable is Mite (http://mite.keynote.com/)
What a great tool. Mite is a mobile web tester. It allows you to view multiple device views of your site. It also does performance evaluations, scripting, and testing. I can’t say enough good words. It allowed me to find a bug and other UX issues on multiple platforms. Though I typically use jquerymobile, Mite found an issue with windows phone 7 that I was able to correct.