Right.
The appradio allegedly works. When I bought mine it supported iPhone 4, I had iPhone 5. It streamed music and calls via Bluetooth and via a USB cable no problem from iPhone 5, but app radio (including playing media like videos) had none of it - not even from my 32-pin iPad. I believe a new version of firmware now supports iPhone 5 and a lightning cable, however, make sure you read up and get the kit if you have iPhone 5. It needs not only a cable from Pioneer but also the av cable from apple to make it all happen. For me, I can't be arsed to buy kit, take it out and upgrade firmware - all for the novelty of streaming video and a few apps. The HU touchscreen is ok, but not even close to iPhone, so if I want to use apps in the car (very rarely) I just grab my phone and save 10 minutes messing about!
In short, make sure your phone works with your firmware and cables, if you upgrade firmware, do it before you install. The USB is round the back, which looks nice but isn't easy to reach. For some rubbish reason you can't upgrade firmware from a cd or dvd.
Have a look here http://www.pioneer.eu/uk/support/software/tax/946/page.html
and here http://www.pioneer.eu/uk/products/25/38/301/CD-IV202AV/page.html
Good luck with it!