Login error
In case you stuck on Clara(?) loading screen
*for smartphone user
1) Just like others said, clear your user data from 'Setting > Manage apps > Clear all data (not uninstalling the app)
2) Open the app & authorize login again.
For my case, after authorize my screen stuck & slightly blinking. Force close the app (& close the apps tab too)
3) Relogin & download package (maybe about 260 mb). In my case again, the language reverts back (to chinese) & my main page back to Harang. Just set it back to your preference then.