iphone 4 high res startup image

I have a fullscreen iphone web app that has a startup screen that works. I am trying to figure out how to get this image looking better on the iP4, but if I change the size from 320x460 it simply will not lo开发者_如何学Goad.

Anyone find a solution yet?

Thanks, Peter

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You need to have a second image with the ending @2x.

For example, if your startup image is named Default.png, your high-rest image should be named Default@2x.png