The problem is the execution environment for mobile devices. It simply varies too much. For desktop browsers it was fairly easy to come up with a page that worked well with every browser I thought to try. Mobile sites have so far frustrated that desire. What I have works on my iPad, but no friend’s smart phone has made it work likewise. Some don’t let one zoom in at all. Some zoom in but always draw the dots ridiculously small (despite their being specified as 4 pixels in diameter). Some don’t register touches that call the touch callback. And so on.