At its developer’s conference yesterday, Apple announced that the next iOS update will feature Do Not Disturb While Driving mode. It will let the phone detect when you are driving using your bluetooth system or wifi, keeping the screen dark and the volume muted. You also won’t be able to access apps.
It can also let people know that you're driving with an automated text. Of course, you can always turn the feature off by clicking the button “I’m not driving.”