Claudius Kirsch from Germany just released a small application which brings the WFDF Ultimate Rules to your iPhone. It's just the right thing if you need a quick look at a certain passage between games. And of course a good chance to show your newest gadget to your teammates!
Here's the iTunes link which brings you to the free app: http://tr.im/BS5w (make sure you have iTunes installed on your PC before clicking the link)
The app is pretty easy to use and allows to view the rules in portrait or landscape mode. The text is zoomable and you can switch between translations in the app. Right now this includes English and German. More languages may follow.