This seems to have been tried by others - from what I can tell, AVIC feeds (whatever they really buy you) run/can be updated via Bluetooth. I'm no AVIC Feeds kinda guy - so I'm not getting (understanding) that add on.
We did try (others have also) to connect via the iPod cable - and you get the standard 'incompatible' Z110/iPad statement.
We did find that at least (which is not bad) - you can connect nicely via Bluetooth audio. This allows very good sound quality. The negative side is the sound via iTunes is *clearly* not Dolby (any version of surround). I think it is really not all that bad on some video - but generally, not close to a real digital source. At least you still have the large screen - so I guess a real 'iPad' connection is not that big an issue.
So Bluetooth - fine. You can stream Youtube (via Bluetoth audio using the iPad as a screen) - but real integration just does not exist.....
Wish Pioneer moved this more into the main stream - at least then they'd get real support (software), and likely a hugely marketable following...
That's my $.02.....