Square Enix shouldn't focus on iOS/mobile games.
When I play games on my iPhone they last 1-5 minutes per session. I never played an iPhone game for longer than say 10 minutes.
That's why rpgs like FFI-III and TWEWY won't work on iOS. The iPhone is meant for short games, just pick up and play while waiting for the bus.
20-30 hrs RPG wont work, the iPhone isn't designed for that. If you play TWEWY on your iPhone for 2-3 hours, you'll be left with an iPhone with an dead battery for the rest of the day