My favorite feature: The Team-Mode, where you and friends can battle it out. Great when hanging around with a bigger group of friends, you can split up for a set amount of time and see, who gets the most points.
I am not affiliated with the app, but really enjoy it and thought that you guys might like it as well. Have a nice day!
Yea, right? And you get links to apps/websites which use OSM. Most of them I have never heard of or found while googeling.
The OpenSource Community is the best part of the web, maybe even the last good part.