Why use your own phone?
Use the built in phone and log in with your gmail account (or heck, even finger print) and automatically download preferences and settings automatically...
One forward facing camera? What about side view or Rear view for that matter.
I understand the use of a phone as it is small, cheap and has a lot of computing power. Today's smart phones are hilariously underutilized IMHO.
And I do like the idea of sharing cars. Especially a car which is able to drive to where you are and then takes you from A to B. The biggest problem is that either everyone has auto-drive, or no-one. Human error will be the major influence into getting this tech onto the open road and you can only get stats when driver-less cars actually roam the earth.
Maybe these kids will get a job offer from Google as they have been experimenting with driver-less cars for a while now.