How do you expect the user to login ? Why constantly checking if he is logged in ? If you are using sessions/cookie, you could just refresh the page at fixed interval, if he is logged in from different tab in same browser, this would pick that up.
As i said you could just reload the page or check the same with ajax. Ofcourse, this would work only if same session id is set for both the tabs (highly likely scenario unless something is screwed up).
Yes, but my app is into iframe at other website, so I try first to open facebooklogin in new smaller window and after that to chech on iframe window when is user loged to redirect them... so iframe is my problme
Can you add a submit button to your iframe that the user can click once logged in. If app is running in iframe authentication should also work in the iframe, just like a browser window.
Using javascript is nice and all, but you should not rely on that, and always use php to double check wether or not the person is actually logged in.
Since all Auth::check() does is return a true or false, that should be quite easy to manipulate browserside.