The DS has something called "Kingdom Hearts 358/2 days". In it, you play as Organization XIII I believe.
S/E should make an exclusive FF title for the iDevices. I am sure that they sell a million copies. Rumours say that they're working on it.
I guess I'll ask the same question everyone else is thinking, why the hell would SE want to produce an exclusive FF title for iDevices? They'd make 100 times more cash making an exclusive DS FF. With that said, I'm sure SE is hurting right now. FF IV is a complete disaster. As far as I know they've given 2 months free to every player (hundreds of thousands x $30 most likely). Assuming Chaos Rings made some profit, maybe they are just desperate enough.