Wow didn't think this would work!!!
I plugged my powered USB hub into my ipad air and then plugged my Digitech RP155 plus also my USB controller keyboard. When I went to the midi mapping section of loopy both devices where there! I was able to map loopy events to keys on the keyboard. Just thought this was pretty cool since I wanted to use both a wires RP155 and (when I buy one) wired controller footboard. Not sure if this is common knowledge but wanted to share