Tapatalk! Although all the functions don't work on a forum like this. I can't post in a thread if its a sticky. And PM's don't work. Same thing with Overclock.net as they recently went to this type of forum.
But its good enough just to browse some threads.
As far as the mobile site. I don't mess with apple but in android you can put a bookmark link to avs on your home screen. Which really makes it no different than an app since the layout is very similar.