Main function of a car is to move a group of people from point A to point B. Tesla is getting good at it, provided point A and point B are not too far apart, and pint B has an electric charger available. And that is a pretty critical limitation so far.

Jumping on your slightly irrelevant analogies, it is like iPod 5 with a batter that can only hold charge for 30 minutes, and can only charged at Apple store.