IOS icon and default picture naming rules

One, the application picture
The image resources in the standard iOS control, Apple has done a corresponding upgrade, we need to worry about is the application of their own image resources. As with the @2x high-resolution version of the iphone 4, we want to make a high-score version of the images in the ipad app. I know that a lot of developers are very predictable, as early as the iOS 5.0 SDK completed this step of the upgrade. But I'd like to stress that that's what Michael Jurewitz said before: the @Jury.

-If you want your high score to appear on the new ipad, you must compile it with the Xcode 4.3.1, along with the iOS 5.1 SDK.

Second, the application of the icon

The next step is to make a high-score version of the main icon, because the lower-version icon looks miserable on the new ipad desktop. To support more iOS devices and higher-resolution screens, iOS developers need to prepare the main program icon files for their applications, and the file list looks increasingly long and growing ... (Translator: Sigh ~). For more information please refer to the latest Apple Developer Docs iOS App programming Guide and iOS Human Interface guidelines. From the official document, I found what we need to prepare for the retina display of the new ipad:

ipad main application icon (144x144 pixel): Previously used in the ipad 1, 2 generation is 72x72 pixel. Now we need an additional @2x version (144x144 pixel).

ipad search results icon (100x100 pixel): This icon appears in the system search results (translator: Also in the system settings, if the application support). The previous version used 50x50 pixels, and now the @2x version needs 100x100 pixels.

File naming and Info.plist files:
Depending on the minimum version of iOS that your application needs to support, you may need to specify the icon file name in the Info.plist file, or you can name a different version of the main icon file according to Apple's specifications. The saddest thing I'm afraid of is that you're running a general-purpose app that runs on the iphone and can run on the ipad (Universal app), and you're going to support iOS 3.1.x and even earlier versions (translator: In fact, now iOS 4.0 and above the device penetration rate is already very high, There's absolutely no need to support vintage versions, and we're not Android. Since iOS 3.2 does not support the designation of icon files in the Info.plist file, you must use the specification specified by Apple to name the icon file. A complete list is almost as follows:
icon.png–57x57 iphone App icon
icon@2x.png–114x114 iPhone Retina Display application icon
icon-72.png–72x72 ipad app icon
icon-72@2x.png-144x144 iPad Retina Display application icon
icon-small.png–29x29 IPhone System Setup and search results icon
icon-small@2x.png–58x58 iPhone Retina Display System setup and search results icon
icon-small-50.png–50x50 IPad system settings and search results icon
ICON-SMALL-50@2X.PNG–100X100 IPad Retina Display System setup and search results icon

If your application is compatible only with iOS 3.2 and later versions, Then you can specify the icon file in the Info.plist file, you do not have to adhere to the above naming conventions, of course, you have to name it is not a problem (translator: To facilitate and the art of communication and future project resources management, or recommend to follow this set of specifications). In iOS 3.2, Apple introduced the Cfbundleiconfiles key in the Info.plist file, where you can specify the various versions of the application icon directly. If you ignore the. png suffix name, you can also ignore the @2x portion of the highly-divided version of the picture, and the system will automatically match.

Apple has again introduced a new key cfbundleicons in iOS 5.0 to support the magazine (newsstand) function, which makes things more complicated (translator: Sigh again). This key contains the subkey Cfbundleprimaryicon, inside the Cfbundleiconfiles key to save the contents of the Info.plist root node cfbundleiconfiles key. If your app only supports iOS 5.0 and later, use a cfbundleicons key, otherwise you'll need to keep the Cfbundleiconfiles key and related content.

(Translator: Here the original story is slightly biased, not mentioned cfbundleprimaryicon, and more confusing, puzzling. In fact, in Xcode the default way to open the Info.plist see will be icon files and icon files (IOS 5) two sets of keys)

In short, in order to be backward compatible, this link will bring a little confusion to the developer, it is quite easy to make mistakes. Therefore, developers are advised to do more testing for different devices and screen combinations.

Third, the application shop screenshot picture

Apple has recently made a regular adjustment to the application submission, and if it is an iphone, ipod Touch app, it must submit a Retina screen shot of the high-score version of the app. The specific picture size requirements are as follows (the front size is a screenshot with the System status bar):
-Horizontal screen: 960x640 or 960x600
-Vertical screen: 640x960 or 640x920

Apple has not yet made a similar request for ipad apps, but it's time to consider using a high-resolution screenshot to make your application screenshots appear on the new ipad. The corresponding screenshot size is as follows (the previous size is a screenshot with status bar):
-Horizontal screen: 2048x1536 or 2048x1496 pixels
-Vertical screen: 1536x2048 or 1536x2008 pixels

Translator Note: Someone in the original comment added that the Run-time loading screen also needed to be prepared for the new ipad screen, file naming and size requirements:
-Horizontal screen: default-landscape@2x~ipad.png (2048x1496 pixel)
-Vertical screen: default-portrait@2x~ipad.png (1536x2008 pixels)