Although i have had an iPad for about 6 months now, i never bothered to try it with the USB integration on the factory unit. Well, I just did a basic test and it works fine! I didn't get a huge GM logo displayed on it (the iPod app showed an "Accessory connected" icon and at least initially, the album artwork was displayed alongside), the game i was playing at the time was still playable so it looks like another alternative music source is available.

Couple things to note:
1. This is using the latest iOS release 4.3.3 (IIRC)
2. Charging may be an issue, since iPads are power-hungry compared to their iPod brethren. I get "not charging" displayed on the iPad when I have it hooked up to my PC, but eventually it does get a full charge, just not near as fast as when it is plugged into its charging unit
3. Since I don't have a 3GS unit, I don't know if a nav application would work at the same time.
4. Playing a game with sound came over the speakers at the same time the iPod-hosted music was playing. Just mute the game sounds unless you want to share. :-)
5. I fired up a music synthesizer program and the iPod-hosted music paused. I could play the synth thru the car speakers. Once i was exited out of the synth app, i used the radio "pause" softkey to resume playback (had to mash the softkey twice, I may have just been impatient).
6. Do you really want to take an expensive piece of kit like the iPad mobile when iPods are cheap and smaller to stash? (I have been thinking about trying to make a pocket for the inside of the flap that covers the seat mechanism next to the console so that an Ipod can be stashed safely out of sight and be protected at the same time.)



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Now playing: Parsons Project, The Alan - Pyramania
via FoxyTunes