I bought FFI for my phone a while ago. I didn't mind playing it on my phone, but I didn't get very far into it due to frustration and lack of direction. I don't think I'd mind playing the older games on my phone, but I'd probably draw the line at VII and up (actually, maybe I'd make that V and up, even though the graphics in V and VI were still 2D and whatnot), just because it seems the games get so much more involved (graphically and story-wise), and to be honest, I'd much rather play an updated version of VII on a big, beautiful TV screen than my tiny phone screen. All of that said, if I'm going to play IV, it'll most likely be on Force's PSP. Bigger screen than my phone, plus the updated graphics, anyway.