I'm a web developer and I've implemented Oauth a couple times. I would forward the user to a login screen on a third-party page, then it would send the user back to my server.
But I'm making an android app (using flutter) at the moment, and I'm confused. Do I do the same thing? Do I start a web server on the users phone, then send the user to a sign in page then let the server handle the user coming back?
These seems complex for an app. Or am I thinking of this wrong?
Extra:
On flutter, it's very frustrating because when the user finishes authenticating, they are taken back to my server and I now have to close the web browser for them... which is difficult to do since the in-app browsers don't run javascript where I can just run window.close(); in it.