Have you ever been disappointed in the musical selection at a bar? Want to put Motörhead’s “Ace of Spades” on repeat all night but can’t find it? Can’t stand listening to country music anymore? If the bar has it, the Secret DJ App for the iPhone could fix all your problems. A combination of Foursquare and Spotify (or any other music streaming app, really), Secret DJ lets you check in to business and remotely control their jukebox. If you ever become “mayor” your musical stylings will go to the top of the queue. It also tells you what’s going on nearby, allows you to buy in iTunes or save to Spotify and even preview songs before you select them. We could easily see this being one of the few location-based apps we’d use regularly… when more bars in the US adopt it.