As I understand it, as long as you're hands-free, you're good to go. I do not text ever so that's not an issue. I answer the cell when driving but that's done with a push of the button on the Plantronics earpiece. I throw the iPhone onto the passenger seat where it stays when I'm driving.

As for this heads up display, other than putting the information on your windshield, it's not much different than the Garmin Nuvi I use all the time; the difference being it uses a cellphone for nav input rather than the Nuvi's dedicated GPS receiver and the Nuvi has a lot more information on the display.

I'm thinking I'd rather have a dedicated GPS and keep my iPhone for taking calls.