There are a lot of apps out there that show you were you have been already, but non that shows you where you haven´t been to. The Hopscotch app lets you explore the uncharted.

You can track your trips and hikes in many apps, but known of these apps will show you the unknown, yet to explore terrain. That´s where the Hopscotch app comes in. The handy app shows you a blank back screen when you open it the first time. But as soon as you walk around, it will track your trip and picture it on the screen. So you always see, where on earth you haven´t been.

It remains me of the Fog of War concept used in many old strategy or adventure games (remember Starcraft, uh?). May the developers thought the same and brought a nice gamification element into the app. With every 100m square of earth you explore, you get 1 point. You even can compete your points in a global leader board. So you see who is the best explorer among your friends.
I like the simple but smart idea. The handy travel app is ready for download but you can neither sign up or login, as it is still in beta. There is also no Android app yet.
Anyway, I´ll try it out, when the guys release their app.