IOS application icons change when the system will default after upgrading IOS7

IOS ask a question,

I had developed IOS application, when upgrading your system to the IOS7, the icon will be applied becomes the default. As shown below:


Because I lack the sake of what format images do? Because I see the icons of other applications after upgrade IOS7 remain.

Ask those pixel icon is a must do, if you want to do in ipad, iphone through those pixel icon is a must,
Has been plagued for several days, thank you.
Reply:
Ah, I have encountered a few days ago this problem, but only have this problem in the 6.1 system
Reply:

cited a floor chewei830 reply:

ah, I also encountered a few days ago this problem, but only have this problem

Do you mean what does it mean? Development occurs when the specified target is 6.1 problem?
Thank you.
Reply:
Not, plist file which you want to add several sizes of icons like
Reply:
Finally, in the foreign forum asked to answer.
http://stackoverflow .com/questions/19443367/why-apps-icon-disappear-after-update-ios7/19443679? noredirect = 1 # 19443679