Play game with FB friends

I am working on multiplayer game for which I want to add functionality related to facebook friend invitation.

For this I have implemented friendsmash-unity example provided by facebook and it work as expected.

At present in game player can send request to his friends and friends receive his notation and move to game.

Now I want to add functionality like connected friends play game in same room. I want some suggestion regarding this implementation and only concept become enough for me.