Apple now require that a 1024×1024 icon is submitted for the App store. Where can I see an example of where this icon is used? The largest icon I can find in the iTunes store is about 180×180 – even on a retina screen, 360×360 would be sufficient.
I am putting some time into designing a large version of my icon, but if it is going to then be shrunk down, I need to design for this, no?
The large version of the icon is used to generate smaller versions for display in the app store and in other places that require icons in sizes other than the ones you submit. That way, if they need a version of your icon that’s 162 px square, or 204 px square, or whatever, they have plenty of pixels in the larger version to ensure a reasonable rendition at smaller size.
Apple used to require a 512 x 512 px icon for this purpose — sounds like they’ve doubled the resolution to support retina displays.
Remember, we’re talking about a megapixel image here, not a 32 x 32 px tiny icon. When you’re dealing with teensy icons, you do have to hand tweak each pixel to get the best approximation of the image you’re trying to represent. When you’re talking about scaling from 1024 px square to 360 px square, there shouldn’t be a problem unless you’ve added some very fine detail at the large size. Don’t do that.