I think it might only need internet when you're accessing a new realm for the first time. That's the only time it ever gives me a download message.
Well, whenever I'm not connected to WiFi I can't even access the game.
That's lame. : /
This is the first mobile game I've ever spent any real time on. I'm fortunate that my wife decided she had to have an iPad for Christmas or I wouldn't even be able to play it.
I'm discussing my 108, er, 111 favorite games of all time in THIS THREAD so go check it out and join the conversation!