Shell scripts to generate all required app icons and launch images on iPad and iPhone.
See
iOS Human Interface Guidelines Custom Icon and Image Creation Guidelines https://developer.apple.com/library/ios/#documentation/UserExperience/Conceptual/MobileHIG/IconsImages/IconsImages.html
Technical Q&A App Icons on iPad and iPhone http://developer.apple.com/library/ios/#qa/qa1686/_index.html
Passbook Programming Guide Images Fill Their Allotted Space http://developer.apple.com/library/ios/#Documentation/UserExperience/Conceptual/PassKit_PG/Chapters/Creating.html#//apple_ref/doc/uid/TP40012195-CH4-SW52