Preparing assets for the iPhone 4 can be a tricky business when you need to ensure you've created the retina display assets as well as the standard resolution.
For anybody that doesn't know what I mean; the iPhone 4 has a retina display which is basically (and conveniently) twice the resolution of the older iPhone screens.
When developing an app for the retina display all the developer has to do to cater for these two resolutions is to ensure that there is a copy of every asset produced at twice the size in pixels with the filename appended with '@2x' (I remember this by thinking of it as 'AT
