On: Neat trick for getting private info for Facebook, ...

[abraham]

Twitter provides an undocumented endpoint that returns true/false depending on your session state.

  <script>
    function twitterSessionsPresent(state) {
      console.log(state);
    }
  </script>
  <script src='https://api.twitter.com/sessions/present.js?callback=twitterSessionsPresent'></script>