title: Facebook SSO with App Login
body: <p>So I have an app, I want users to create a login within my application and then after logging in have the option to connect their facebook to the app/their account.</p>
  
  <p>The problem is: <strong>If user1 logs out, and their friend (user2) wants to create an account on user1's phone. Then once user2 logs it, it will try the Fbook SSO for user1 even thought it is user2 logging in.</strong></p>
  
  <p>I'm looking for a way to check the fbook app to see which user is logged in, and then have my app only SSO when the correct user logs in from my app.</p>
  
  <p>Any suggestions?</p>
  
  <p>====</p>
  
  <p>Let me clarify, I don't want user1 and user2 to be able to login to facebook. I just want to make sure that fbook sso only happens when user1 logs in.</p>