Audiobus: Use your music apps together.
What is Audiobus? — Audiobus is an award-winning music app for iPhone and iPad which lets you use your other music apps together. Chain effects on your favourite synth, run the output of apps or Audio Units into an app like GarageBand or Loopy, or select a different audio interface output for each app. Route MIDI between apps — drive a synth from a MIDI sequencer, or add an arpeggiator to your MIDI keyboard — or sync with your external MIDI gear. And control your entire setup from a MIDI controller.Download on the App Store
Audiobus is the app that makes the rest of your setup better.
What to use for live use - advice sought please (with my wish list) ...
I'm currently using a single keyboard controller and my iPad for all sounds. I saw iMidiPatchbay before I saw AudioBus, so I'm using that, with quite a number of preset 'songs' (really used more as patches in my case).
This works quite well but iMidiPatchbay doesn't start up the applications I'm using in the background, so I need to remember to start them all separately. Also cannot easily switch to them and back without using the iPad home key task switching, which is more fiddly when playing live. Currently I'm using iGrand, Korg Module, SampleTank, Sunrizer, Galileo and Thor and looking to add a few others for specific sounds, so it's a bit of a pain to start up for a session.
Once up and running, it's mostly fine, though the display could be better for me if a little different.
Now I've looked at AudioBus and it has the facility to start referenced apps in the background (if I understand right) plus some extra facilities for midi routing (e.g. filtering on note velocity for variable layering as well as note value for keyboard splitting), but it doesn't look to be as geared for live interactive use for switching sounds/presets. It also seems fiddly for setting up routings where iMidiPatchbay is all driven from the one screen (but this could be just familiarity).
I'd be interested to know what people use for a live type of environment, as opposed to a more static studio setup. I'm happy to try AudioBus but want to get most benefit from it.
Also, I'm looking to use a USB keyboard (lighter than my old, full keyboard) with the iPad, but concerned that the power draw of the iPad powering the keyboard (and running all those apps) will be too much. Do people use a powered USB hub to charge the iPad and power the keyboard whilst enabling comms between the two? Is there a particular brand that works well - I looked at the one in the 'recommended kit' thread but it's no longer available and whilst there are many that claim to be okay, I'd rather use something with a relevant recommendation.
Sorry for the long post, many thanks to anyone who gets this far and feels like offering any advice/experience.