There are iOS apps that let users access vBulletin boards in an interface environment that is better suited for iPhone, iPod touch and iPad. They require however, that forum owners register the forum with the app and then this particular becomes accessible to app users. I don't know if anyone has looked into it, but it might provide a better experience for mobile users.
There is an app that does not require any server registration, and .Org is easily accessible there, but you can only read in app. If you want to post it opens a Safari browser with that takes you to the regular .Org page. This app is:
Forums Pro http://itunes.apple.com/us/app/forum...399481912?mt=8