So turn-by-turn directions are great and all, but they only work if you're outdoors. What would be cool is if there was an app that allowed the user to navigate to a point inside a building. Obviously, GPS would be useless here. Im thinking maybe the app could ask the user where he is, then use the gyroscope and accelerometer to determine where the user is. Imagine this: Someone's going to be staying at your house, but you won't be there to show them where your bathroom is or where they will be sleeping. No problem. Just send them a file giving directions from the entry points you will allow them to use to your bathroom or to their bedroom. When they get there, they load the app. "Walk forward to the stairs." At stairs: "Walk up the stairs to the second floor." At second floor: "Turn right." "Your bedroom is on the left, at the end of the hallway." Or, a more likely scenario: You're shopping at the mall and want to pick up an iPad as a wedding gift for your sister. No problem. Just tell the app where you are now and it will give you turn-by-turn directions to a store in the mall that sells Apple products.