Commit to AppStore:1024*1024

//for App Icon
Icon-60@3x.png:180*180 //iPhone 6 Plus (@3x)
Icon-60@2x.png:120*120 //iPhone 6 and iPhone 5 (@2x)
Icon-76@2x.png:152*152 //iPad and iPad mini (@2x)
Icon-76.png:76*76 //iPad 2 and iPad mini (@1x)
Icon.png:57*57 //iPhone Non-Retina (iOS 6.1 and Prior)
Icon@2x.png:114*114 //iPhone Retina (iOS 6.1 and Prior)
Icon-72.png:72*72 //iPad Non-Retina (iOS 6.1 and Prior)
Icon-72@2x.png:144*144 //iPad Retina (iOS 6.1 and Prior)

//for Spotlight search results icon
Icon-40.png:40*40 //iPad Non-Retina
Icon-40@2x.png:80*80 //iPad Retina
Icon-40@3x.png:120*120 //iPhone 6 Plus

//for Settings icon
Icon-29.png:29*29 //iPhone Non-Retina (iOS 6.1 and Prior)
Icon-29@2x.png:58*58 //iPhone Retina (iOS 6.1 and Prior)
Icon-29@3x.png:87*87 //iPhone 6 Plus
Icon-50.png:50*50 //iPad Non-Retina (iOS 6.1 and Prior)
Icon-50@2x.png:100*100 //iPad Retina (iOS 6.1 and Prior)

iphone 应用需要包含iphone的图标尺寸和ipad图标应用尺寸(因为iphone应用可以运行在ipad上)
ipad 应用只需要包含ipad的图标尺寸。（iPad应用不能在iPhone上运行，因此iPad应用有专属自己的图标像素。）

iOS App Icon图标 尺寸规范