I've been re-checking out Group The Loop and as long as I don't use Audiobus it seems to work fine on my iPad2 with other apps via IAA. I can play Bias Amp quite nicely with it and was really impressed yesterday.
However my favorite guitar amp sim is Tonestack. I might be missing something, but Tonestack has a bunch of IAA features and thought it was IAA compatible? I'm not seeing it on the list of available app inputs in GTL.
So, is this a question for Group The Loop or should I be contacting Yonac, the Tonestack developer, to determine why it isn't showing up as an IAA input?