There are also a number of inexpensive cameras that are not necessarily designated as digital cameras for kids that still work well for children, such as the Kodak Easy Share C310 camera with 4.0 mega pixels.
In looking at this Palm Pre vs. iPhone comparison, the screen appears to be very similar on the two devices.The Apple iPhone 3GS has a 3.5-inch multi-touch display with a resolution of 320x480 pixels.
You will also need to resize the image, both in screen dimensions (For example, 200 pixels by 200 pixels is a nice small square on a web page) and also in resolution - that is, dots per inch (dpi).
DirectX consolidated a thousand different video standards, giving programmers more time to concentrate on the game instead of worrying about how to blit pixels on different kinds of videocards.
As with the number of mega pixels, a preview screen may not be an issue for a very young child, but older children may be disappointed with a camera that doesn't offer this convenient option.