I was playing around with my iPod Touch in the car the other day and found out some interesting things...
When connected to an Alpine 'Made for iPod' head unit via dock connector:
• MobileMusic.app and whatever app plays back videos are unavailable - white 'Accessory Connected' screen.
• MxTube will play back videos with sound through the Alpine, the music even pauses automatically.
• Keyboard sounds are not transmitted.
This is interesting since there are a couple of things I hope to be able to use the iPod Touch for in the future:
• Video playback with sound through the car's speakers. This isn't possible using the built-in video player, but it seems that a third party video playback app would work (and one with support for other codecs would be even better).
• GPS - a company recently demoed a wifi GPS dongle for the iPhone/iPod Touch that would interface with a native app running on the unit. A wireless dongle would leave the dock connector available for music playback through the Alpine (and possibly allow for sound from GPS software) as well as charging the unit.
We shall see how this all pans out, but there is certainly potential here...