Read original post by David Kelley at HackingSilverlight
I'm not sure I'm an expert at HTML phone apps yet but I do strongly believe that just about anything is possible and that there must be a solution to this gray box issue on phone 7 (wp7). So I took on the task of seeing what I could do. I started with creating a new phone 7 app that used my HTML Application Host framework etc (blah blah blah setting up stuff etc) so I got to the point of having my index.html page and started my tests in #wp7.