Not all of us are willing or have the money to purchase a GPS unit for our cars, and there are still some car owners whose vehicles do not come with built-in GPS systems either, meaning that in some cases, we still need to use our phone to check Google Maps or other GPS apps to find our way around unfamiliar areas. Naturally this can be pretty dangerous and it seems that a Californian judge thinks so as well and has made it clear that driving while checking maps on your phone is considered illegal. Basically the judge viewed the checking of maps as equivalent of using a phone while driving, hence the ruling.
Ubergizmo , Judge Rules That Checking Maps On Your Phone While Driving Is Illegal, Judge Rules That Checking Maps On Your Phone While Driving Is Illegal