Be the master of puppets while your friends are just dancing.
My only Just Dance experience has been the first game. My takeaway from it then was that it was a silly dancing game that was fun even though the recognition of your moves seemed wonky. Just Dance 4, coming to Wii U at the system's launch, continues that tradition of somewhat-wonky dance move recognition with fun, while adding the new Puppet Master mode.
The Puppet Master mode allows one player to select dance moves for the others to perform by using the Wii U GamePad's touch screen. It is simple, but it's entertaining, especially since the name and animation for the moves are humorous, featuring zombies, a person with a TV on their head, and more. Occasionally, you have the option to select a pose for the players to hold, and then you judge who did the best job at holding the pose. You can be somewhat diabolical and make everyone hold a pose that requires good balance.
The Wii U GamePad can also be used to select songs, so it makes for an easier way to select songs from the game's soundtrack, which includes songs like "Moves Like Jagger" by Maroon 5, "Never Gonna Give You Up" by Rick Astley, and "Wild Wild West" by Will Smith.