I have an android game built with libgdx and what I'd like to do is to add some kind of authentication so I can connect the game with user data to firebase database.
I have some experience with firebase using it in native android apps, but I have no idea on how to connect "native code" with libgdx.
Researching I found these third party libs https://github.com/mk-5/gdx-fireapp/tree/master/gdx-fireapp-core and https://github.com/TomGrill/gdx-firebase
But as it does not provide any example it didn't help me much.
So what's the best way to "mix" native android code and libgdx? I want to be able to achieve things like storing data on db, implementing in-app-purchases, authenticating users. If I'm looking the wrong way please let me know too.