JapUp Pro (currently %50 off: $9.99) is the best guitar/bass multi-effect processor app for iOS. I’m not the only one who thinks so, check out its iTunes reviews… As of 12/26/11 (when this post was published) it’s ‘Current Version’ and ‘All Versions’ ratting are both 5/5 stars!
UPDATE: This can actualy be done! If you look closely in the very beginning when I drag the amp off of the signal path, it slides right back to it’s original location, but turns gray. Making it inactive…
The one thing it needs though, is the option to not use an amp in the app. Then you’d be able to output your interface into your own amp. Now some interfaces, like Line 6′s Mobile In, don’t have an line out, but if you’re using the Camera Connection Kit and an audio interface, this is definitely possible. Anyway, the developers probably won’t add this, as it is somewhat of a small request, but I bet a lot of people would do it if they knew they could…

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