I still had the old set-up (with some additions), so I took another picture to compare the iPhone 5's resolution. Here's the old picture taken by the ZR200, to compare lighting:
Casio Exilim EX-ZR200 ISO 200 F3.0 exposure 1/25 seconds.
Exilim's exposure control seems better.
I added iPhone 5's crops to the original 3 images:
iPhone 5's camera is clearly better than iPhone 4's, and could even be better than ZR200's 5 MP normal quality mode, if the exposure were better. I agree, exposure shouldn't be the limiting factor to compare resolution, I need better lighting.