The "Glee" Karaoke app is like a little joy-generating machine you can slip in your pocket. Inspired by the Fox hit "Glee," the app allows you to sing along with hit songs, of course, but the sharing and gaming functions are where the user interface really shine. For instance, amateur singers who want to put their crooning up against the warbling of other players around the world can compete on a daily leaderboard after mastering their performances.
There's a tidy recurring revenue angle to this app's business model, too: new songs are released every week (complete with lyrics, pitch timings and harmonies) and can be purchased in-app for 99 cents a pop. And closet rock stars around the world clearly love it: They've used "Glee" Karaoke more than 6 million times so far.