一.准备资料
1.icon图标：
iphone：114*114:icon@2x.png 和57*57:icon.png
ipad:72*72:icon.png
2.启动图标
iphone: Default.png , Default@2x.png
ipad:
Default-Portrait.png iPad专用竖向启动画面 768x1024或者768x1004
Default-Landscape.png iPad专用横向启动画面 1024x768或者1024x748
Default-PortraitUpsideDown.png iPad专用竖向启动画面(Home按钮在屏幕上面)，可省略 768x1024或者768x1004
Default-LandscapeLeft.png iPad专用横向启动画面，可省略 1024x768或者1024x748
Default-LandscapeRight.png iPad专用横向启动画面，可省略 1024x768或者1024x748
为了在iPad上使用上述的启动画面，你还需要在info.plist中加入key: UISupportedInterfaceOrientations。同时，加入值UIInterfaceOrientationPortrait, UIInterfacOrientationPortraitUpsideDown, UIInterfaceOrientationLandscapeLeft, UIInterfaceOrientationLandscapeRight。
二.常见错误
1.iphone/ipod touch application executable is missing a required architecture at least one of the following architecture must be present armv6
解决:
For some reason the default architecture settings with xCode 4.2 is only for armv7. Go to Target -> Build Settings -> Architectures -> Release on value dropdown pick "Other...",
remove $(ARCHS_STANDARD_32_BIT), and add 2 rows first with "armv6" and second "armv7"
Done
2.防止和系统名字函数同名的类或者方法