Not sure why this is a problem. Purchase one of the several clips made for two microphones and run your cables back to camera and ipad. Or just use a single clip for each mic.
You could run a single mic cable to a mixer, then cables out from the mixer to the camera and ipad.
Finally, there are "Y" adapters on the market that would allow you to plug a mic, then split the signal out to two recording devices but this is still going to leave you with two cables running back to your devices. And it's quite likely that doing this will reduce the quality of the signal coming from the mic.