title: What is the oauth_token in signed_request used for in the Facebook App flow?
body: <p>Is it possible to request the access_token using the oauth_token and, say, the app_secret, somehow?</p>
  
  <p>(If not, what on Earth is the oauth_token for?)</p>
  
  <p>Or do I need to make an oath-request each time a user (new session) visits my page to obtain a code for access_token retrieval?</p>
  
  <p>(If yes, how do I enable a smooth user experience for returning users? I do not want to send them back and forth through jscript redirect, yet at the same time I would like to stay in the FB iframe)</p>
  
  <p>Best regards,</p>
  
  <p>SD</p>