Since the last update of the app I can’t connect to sites anymore. It looks like the app does not get the access token. I can see it in my user preferences, but the app still shows the “Connect” button after pressing “Authorize”.
I can use the sites without any problems within Chrome itself, so it’s just a problem with the app.
Also, notice that it now shows “Discourse - Unknown” instead of “Discourse - <Device Name>” when it asks for authorization.
Tested on Android 7.0 and Android 8.1 with Discourse app 1.2.0 and Chrome 63.