Cloak – Incognito Mode for Real Life
http://usecloak.com/

Avoid exes, co-workers, that guy who likes to stop and chat — anyone you’d rather not run into. 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. This will be added to Privacy Resources Subject Tracer™.