How do I see friend scores? So confused!

[jonesjb]

I use the iPad version.Under the individual table, when I select "Leaderboards" the only person there is me. I don't see my friends or their scores, where is the app sourcing this friend list from? Facebook, Farsight, Gamecentre? I'm confused! What do I need to do to fix this.

Thanks to all who can help!