What are the radii of the iOS icon corners? What are the radii of the iOS icon corners at the various sizes?
There are a variety of iOS icon templates available for free on the web—the best I've seen so far is from The Hicksenian—that will offer up this information (and possibly even obviate the need to know entirely). There is even a (very) short discussion about the corner radii. A quick search for ios icon template will return a lot of similar results.