Sometime I play a keytar (lucina) at shows instead of the kb. It's a lot of fun and a lot lighter to lug around than the kb! I also have a rack system I can hook it up (which sort of negates the lightnees factor of the keytar LOL) to and use that with midi instead of the preset sounds. It's great and a lot of fun but I still have wires so I wanted to go wireless with the midi.
So I came up with this :
Basically midi out from the keytar via an iRig midi interface to an iPod running the midi bridge app that sends it over wifi to my iPad running another copy of the midibridge app then via another irig interface to the rack system (XV 5080). The ipod will live in a crrier on the keytar strap giving me freedom to roam.
Now you might say that I cannot guarantee there will be wifi but I figure I can get a router and just configure it to create a local hotspot without internet acccess. It will let the ipad/ipod talk to each other and because it's wifi, I'll get pretty good range if my home network is anything to go by.
Anyway, I've tried this on my home network and it's pretty awesome. Pretty much no delay and with the iRig adapters I can charge the iPad and even maybe use an external battery pack with the ipod/keytar.
Downsides so far are that the vol control on the lucina does not send midi out so I've no volume control to the rack from the keytar although I can hook up my fcb 1010 pedal to the effects unit after the xv 5080 and do it that way, but I might be able to hook up a stomp style midi box to flip flop the volume if I can get the midibridge to accept two wireless signals. That parts all still experimental at this stage.