Icons not appearing on iPod; do appear when using simulator

After building my application and releasing it to my first device for testing, I noticed that a couple of the PNG files are not showing up, as though they don't exist. They appear fine in the simulator. For 开发者_如何学JAVAtesting purpose, I just copied couple of PNG files from a book, and replaced mine with those. The PNGs from the book appear fine, so I tend to think that the way I created my files is not correct.

Is there a special way of saving PNGs? Do they appear differently in the simulator vs real devices?

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iOS Devices have case-sensitive file systems, whereas the simulator does not. That means any of your code which loads/saves any images, including XIBs, needs to be checked to ensure the casing is identical with the file.