I love this! And it's free! Cloak - Cloak scrapes Instagram and Foursquare to let you know where all your friends, "friends," and nonfriends are at all times so you never have to run into that special someone. Think of it as the antisocial network. We'll be adding more social networks and features in the future, so hold tight and remain on red alert. *Why isn't Twitter included as a service?!?! Well, the location data just isn't there.