I considered adding the aftermarket receiver with Apple CarPlay, but I went with a less expensive touchscreen receiver, since both the Pioneer and Alpine receivers were in the $500+ dollar range.
I added a Pioneer touchscreen receiver that works well with my iPhone 5 (now iPhone 6). Here's the post I made when I installed it in August.
http://myimiev.com/forum/viewtopic.php?f=14&t=509&p=18503&hilit=stereo#p18503
The receiver automatically connects to my iPhone via Bluetooth as soon as I get into the car, giving me a hands free phone and playing all of my radio apps. I very rarely listen to the radio in the car anymore, instead playing music from my phone or listening to radio apps. If I receive a phone call, the receiver automatically turns off the music and displays the call that I can answer using the touchscreen.
Apple has partnered with many car makers, including Mitsubishi, to put Apple CarPlay in new cars. It looks like these CarPlay receivers bring the app icons right to the touchscreen.
https://www.apple.com/ios/carplay/