I got a chance to play with a demo unit at a press briefing Wednesday at the W Hotel in San Francisco.

The AppRadio features an 800-by-480-pixel, 6.1-inch capacitive touchscreen display (Pioneer says this is the first after-market system to use the type of display you'll find on an iOS device) and volume up, volume down, and home hardware buttons. When you connect an iPhone 4 or fourth-generation iPod touch to the unit's 30-pin dock connector cable, you not only get access to the music on it, but also to some of your apps.

I say some because Pioneer has worked closely with a few app makers, who've updated their apps specifically to work the head unit. As of Wednesday, those apps are , , , and (representatives from those companies were on hand to demo their apps).

Pioneer also supports the built-in Maps app, and the company hopes to add more apps by the time the product launches in June, as well as after launch. A free Pioneer AppRadio app enables access to the iPhone or iPod touch's data and connectivity.

In playing with the apps, I found that the larger screen made using them much easier. With the Inrix app, for example, I could scroll through maps with my finger and pinch to zoom in and out (just as with an iOS device). And you can start using an app in your house--choose a route in MotionX or start playing music in Pandora or Rdio--and then plug in and continue what you were doing in the car.