Move over, Candy Crush, there’s a new Facebook game in town. Who’s Tagged? which launched last week and has already been played by 11,000 people, tests your knowledge of your Facebook friends.

It works on a simple idea: we don’t actually know who we’re friends with on Facebook. Whether we simply accept every friend invitation that comes our way, or we’ve forgotten about acquaintances of yesteryear, most of our connections on the social media site are with near-strangers. The goal of Who’s Tagged is to shed some light on this fact in a fun game setting.

Playing Who’s Tagged

The game gives a player pictures from Facebook of his or her friends, and the player must type in the correct friend’s name. Each time a new picture is shown, a timer begins counting down, so there’s not much time for players to rack their brains. They either know the person immediately or they don’t.

“Our game shows that four out of 10 friends aren’t recognized,” Jens De Jaegher, one of the app’s creators, told Wall Street Insanity. “We try to make people aware of the fact they don’t know all of their Facebook friends, and wouldn’t even recognize them if they were standing next to each other in the supermarket.”

And that’s not counting unrecognizeable photos like bitstrips and tag-to-win contests. The game is programmed to weed those out, said De Jaegher. If the game does give players photos that are similarly unidentifiable, people can report the images and improve overall user experience.

Users can expect the game to improve in other ways, as well. De Jaegher said they eventually want to show users their personal statistics from the game. This would give stats on how many friends people know and don’t know, as well as which friends they recognized the least.

Why People Play

De Jaegher and the Who’s Tagged team live and work in Belguim, and that’s where the game is most popular. Still, almost 2,000 of the game’s 11,000 players speak English.

People are playing for all different reasons. Some are treating it like any other game, playing more than 50 rounds a day to try to beat their high scores.

Others treat it as a trip down memory lane. “Every round shows different pictures, including some ‘forgotten’ older pictures,” De Jaegher said. “Most people [have been] on Facebook for some years now, and are also tagged in pictures of their childhood.”

De Jaegher points out that this facet of the game can be eye-opening for some players. “This makes them realize they share pictures of their [entire lives] with a lot of people they don’t really know.”

And if you play Who’s Tagged and decide you need to keep track of the people you don’t actually like, Hate With Friends has got you covered.