Hi, can any one tell me please if I can use midi guitar in the iOS app grouptheloop?
If I’m understanding your question correctly, I’m guessing you wouldn’t use MG “in” the Group the Loop app (you mean this one, correct?), but rather along with it, with both apps hosted in a live plugin host like AUM Mixer or Audiobus.
It looks to me like Group the Loop is intended for use as a plugin or as an IAA app, hence the comment about Audiobus support.
My own preferred setup, on iOS, is to use AUM Mixer as the live plugin host, and within AUM I use MG as the “MIDI input device” for soft instruments like SWAM woodwinds and strings, and then feed that to the looper plugin I like most, which is Circa by Audio Damage. AUM makes it really easy to arrange these plugins in either dirt-simple chains, or conversely whatever crazy switching I want to do between guitar sounds (I also use guitar amp plugins in my AUM sessions) and soft instruments.
And so I’m guessing you should be able to construct a simple AUM session with one “channel” taking audio interface hardware input, passing it to a plugin instance of MG, and sending its output either 1) as MIDI output, to another “channel” with a soft instrument, and/or 2) as audio output (from one of the truly “internal” instruments like the MDA Piano, or just raw guitar passthru output) to other effects/plugins, either downstream of MG in the same channel, or in a different channel. The sound-producing channels, then–your soft instrument which took its MIDI input from MG, and/or the audio that comes from MG and any downstream plugins–all get funneled into a channel with the looper plugin, which then goes to hardware out so you can hear it.
Does that make sense? Again, if I’m understanding your question correctly–forgive me if I presumed something incorrectly–I’d think this is the way you’d make use of both of those plugins/apps on iOS.
(I have been loving MG on iOS, by the way. It’s been kinda blowing my mind. 
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