How to draw an iOS 7 style app icon?

Question

Since the iOS 7 releases, the app icon has changed from rounded rectangle to super-ellipse.

My question is how to draw a super-ellipse in the most effective way? Is there any iOS library/project to implement super-ellipse drawing? Here is the formula mentioned by Remy.

Answer 1

You don't need to draw a super-eclipse.

Draw your icon as a square and Apple will do that for you.

You can use this website to create all icons with the good size and good name for iOS 6, 7 and Android.

EDIT :

But, if you want to design your own icon for a button (for example) you can use this template of .psd