title: Facebook Friends Data for comparison game
body: <p>I have a small question, that doesn't let me sleep for days. 
  You know applications, that compare your profile with your friends, e.g likes, movies, music, etc. How is it possible? I know that Facebook API provides access only for users who already used your application, for non-app users Facebook API provides the special method 'invitable_friends' to send invites, and that's all.</p>
  
  <p>Are these fake applications? </p>
  
  <p>Thanks!</p>