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Technical Q&A QA1686

App Icons on iPad and iPhone

Q: How are the icon files in my application bundle used on iPad and iPhone?

A: Below are guidelines for handling icon files for iPhone-only apps, iPad-only apps, and universal apps.

If you don't provide artwork for one of the listed optional icons, the system will automatically scale one of your existing icon images to an appropriate size. It is strongly recommended that your application include artwork for all the icons listed, at the specific sizes needed.

Prior to iOS 3.2, icon images were required to follow a strict naming convention. These legacy names are still listed in the tables below along with example names for the more recent icons. Except for iTunesArtwork, icon images included in your app can have arbitrary names.

Note: iOS ignores the PPI (Pixels Per Inch) of icon images. You may author your icon images at any PPI but their width and height, as measured in pixels, must match the values in the tables below.

Important: iTunesArtwork icon images should be in png format, but name them without the .png extension.

Icons for iPhone-only Apps

iPhone-only applications use the following icons. Items marked with "Required" must be included.

Note: You should include images for the iPad-specific icons even if your app is not a universal app. If available, they will be used when the app is installed on an iPad.

**Table 1** iPhone-only app icon requirements.
Image Size (px)	File Name	Used For	App Store	Ad Hoc
512x512	iTunesArtwork	App list in iTunes	Do not include	Optional but recommended
1024x1024	iTunesArtwork@2x	App list in iTunes on devices with retina display	Do not include	Optional but recommended
120x120	[email protected]	Home screen on iPhone/iPod Touch with retina display	Required	Required
180x180	[email protected]	Home screen on iPhone 6 Plus	Optional but recommended	Optional but recommended
76x76	Icon-76.png	Home screen on iPad	Optional but recommended	Optional but recommended
152x152	[email protected]	Home screen on iPad with retina display	Optional but recommended	Optional but recommended
40x40	Icon-Small-40.png	Spotlight	Optional but recommended	Optional but recommended
80x80	[email protected]	Spotlight on devices with retina display	Optional but recommended	Optional but recommended
120x120	[email protected]	Spotlight on iPhone 6 Plus	Optional but recommended	Optional but recommended
29x29	Icon-Small.png	Settings	Recommended if you have a Settings bundle, optional otherwise	Recommended if you have a Settings bundle, optional otherwise
58x58	[email protected]	Settings on devices with retina display	Recommended if you have a Settings bundle, optional otherwise	Recommended if you have a Settings bundle, optional otherwise
87x87	[email protected]	Settings on iPhone 6 Plus	Recommended if you have a Settings bundle, optional otherwise	Recommended if you have a Settings bundle, optional otherwise

In addition to the above icons, iPhone-only applications with a deployment target of iOS 6.1 or earlier use the following icons. Items marked with "Required" must be included if the application's deployment target is iOS 6.1 or earlier.

**Table 2** iPhone-only app icon requirements (iOS 6.1 and earlier).
Image Size (px)	File Name	Used For	App Store	Ad Hoc
57x57	Icon.png	Home screen on iPhone/iPod touch (iOS 6.1 and earlier)	Required	Required
114x114	[email protected]	Home screen on iPhone/iPod Touch with retina display (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
72x72	Icon-72.png	Home screen on iPad (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
144x144	[email protected]	Home screen on iPad with retina display (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
29x29	Icon-Small.png	Spotlight on iPhone/iPod Touch (iOS 6.1 and earlier) and Settings	Recommended if you have a Settings bundle, otherwise optional but recommended	Recommended if you have a Settings bundle, otherwise optional but recommended
58x58	[email protected]	Spotlight on iPhone/iPod Touch with retina display (iOS 6.1 and earlier) and Settings on devices with retina display	Recommended if you have a Settings bundle, otherwise optional but recommended	Recommended if you have a Settings bundle, otherwise optional but recommended
50x50	Icon-Small-50.png	Spotlight on iPad (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
100x100	[email protected]	Spotlight on iPad with retina display (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended

You can include distinct images for the iPhone and iPad icons in categories where the required sizes are equivalent, for example, Settings.

Icons for iPad-only Apps

iPad-only applications use the following icons. Items marked with "Required" must be included.

**Table 3** iPad-only app icon requirements.
Image Size (px)	File Name	Used For	App Store	Ad Hoc
512x512	iTunesArtwork	Ad Hoc iTunes	Do not include	Optional but recommended
1024x1024	iTunesArtwork@2x	Ad Hoc iTunes on devices with retina display	Do not include	Optional but recommended
76x76	Icon-76.png	Home screen on iPad	Required	Required
152x152	[email protected]	Home screen on iPad with retina display	Optional but recommended	Optional but recommended
40x40	Icon-Small-40.png	Spotlight on iPad	Optional but recommended	Optional but recommended
80x80	[email protected]	Spotlight on iPad with retina display	Optional but recommended	Optional but recommended
29x29	Icon-Small.png	Settings on iPad	Recommended if you have a Settings bundle, otherwise optional but recommended	Recommended if you have a Settings bundle, otherwise optional but recommended
58x58	[email protected]	Settings on iPad with retina display	Recommended if you have a Settings bundle, otherwise optional but recommended	Recommended if you have a Settings bundle, otherwise optional but recommended

In addition to the above icons, iPad-only applications with a deployment target of iOS 6.1 or earlier use the following icons. Items marked with "Required" must be included if the application's deployment target is iOS 6.1 or earlier.

**Table 4** iPad-only app icon requirements (iOS 6.1 and earlier).
Image Size (px)	File Name	Used For	App Store	Ad Hoc
72x72	Icon-72.png	Home screen on iPad (iOS 6.1 and earlier)	Required	Required
144x144	[email protected]	Home screen on iPad with retina display (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
50x50	Icon-Small-50.png	Spotlight on iPad (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
100x100	[email protected]	Spotlight on iPad with retina display (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended

Icons for Universal Apps

Universal applications use the following icons. Items marked with "Required" must be included.

**Table 5** Universal app icon requirements.
Image Size (px)	File Name	Used For	App Store	Ad Hoc
512x512	iTunesArtwork	App list in iTunes	Do not include	Optional but recommended
1024x1024	iTunesArtwork@2x	App list in iTunes for devices with retina display	Do not include	Optional but recommended
120x120	[email protected]	Home screen on iPhone/iPod Touch with retina display	Required	Required
180x180	[email protected]	Home screen on iPhone 6 Plus	Optional but recommended	Optional but recommended
76x76	Icon-76.png	Home screen on iPad	Required	Required
152x152	[email protected]	Home screen on iPad with retina display	Optional but recommended	Optional but recommended
40x40	Icon-Small-40.png	Spotlight	Optional but recommended	Optional but recommended
80x80	[email protected]	Spotlight on devices with retina display	Optional but recommended	Optional but recommended
120x120	[email protected]	Spotlight on iPhone 6 Plus	Optional but recommended	Optional but recommended
29x29	Icon-Small.png	Settings	Recommended if you have a Settings bundle, optional otherwise	Recommended if you have a Settings bundle, optional otherwise
58x58	[email protected]	Settings on devices with retina display	Recommended if you have a Settings bundle, optional otherwise	Recommended if you have a Settings bundle, optional otherwise
87x87	[email protected]	Settings on iPhone 6 Plus	Recommended if you have a Settings bundle, optional otherwise	Recommended if you have a Settings bundle, optional otherwise

In addition to the above icons, universal applications with a deployment target of iOS 6.1 or earlier use the following icons. Items marked with "Required" must be included if the application's deployment target is iOS 6.1 or earlier.

**Table 6** Universal app icon requirements (iOS 6.1 and earlier).
Image Size (px)	File Name	Used For	App Store	Ad Hoc
57x57	Icon.png	Home screen on iPhone/iPod touch (iOS 6.1 and earlier)	Required	Required
114x114	[email protected]	Home screen on iPhone/iPod Touch with retina display (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
72x72	Icon-72.png	Home screen on iPad (iOS 6.1 and earlier)	Required	Required
144x144	[email protected]	Home screen on iPad with retina display (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
29x29	Icon-Small.png	Spotlight on iPhone/iPod Touch (iOS 6.1 and earlier) and Settings	Recommended if you have a Settings bundle, otherwise optional but recommended	Recommended if you have a Settings bundle, otherwise optional but recommended
58x58	[email protected]	Spotlight on iPhone/iPod Touch with retina display (iOS 6.1 and earlier) and Settings on devices with retina display	Recommended if you have a Settings bundle, otherwise optional but recommended	Recommended if you have a Settings bundle, otherwise optional but recommended
50x50	Icon-Small-50.png	Spotlight on iPad (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended
100x100	[email protected]	Spotlight on iPad with retina display (iOS 6.1 and earlier)	Optional but recommended	Optional but recommended

You can include distinct images for the iPhone and iPad icons in categories where the required sizes are equivalent, for example, Settings.

Adding Icons to Your App

Asset catalogs are the preferred way to manage your application's icons. New projects are configured to use asset catalogs by default. Migrating an App Icon Set or Launch Image Set in the Asset Catalog Help describes how to migrate an existing project to use asset catalogs.If your application must support iOS 4.3, or you prefer not to use asset catalogs, you can manually configure your application's icons by editing the information property list for your application. See Configuring Icons Without an Asset Catalog.

Adding Icon Images to an Asset Catalog

Select the asset catalog in the project navigator. It is named Images.xcassets by default.
From the left column of the editor, select the icon set. For new or migrated projects it will be named 'AppIcon'. You may need to create an icon set by clicking the (+) button in the bottom left of the editor and choosing 'New App Icon' from the context menu.

Figure 1 The AppIcon set selected in the asset catalog.

The set will only contain image wells for icons that are relevant depending upon your project's configuration at the time the asset catalog was created. If an image well is missing, expand the settings inspector and check the appropriate boxes under the App Icon pane depending upon your project's deployment target and supported devices.

Figure 2 Enable the necessary image wells under the App Icon pane of the settings inspector.

Drag images from the Finder onto each image well to configure the associated icon.

Figure 3 Complete icon set for a universal app with a deployment target less than iOS 7.0

Asset catalogs create a copy of images added to them. If you had previously added the images as resources to your project you can safely remove them.

Configure your app to use the new icon set.
1. Select the name of the project in the project navigator.
2. Select the name of your app from the list in the left column of the project editor.
3. Select the General tab at the top of the project editor.
4. Choose your icon set from the App Icons Source popup menu under the App Icons And Launch Images pane.

Figure 4 Configure the icon set for your app's target.

Configuring Icons Without an Asset Catalog

Follow the steps in the Xcode Project Navigator Help to add each icon image to your project as a resource.
Locate your application's information property list in the Xcode File Navigator. By default it will be named <ProductName>-Info.plist, where <ProductName> is the name of your application. Right click it and choose Open As > Source Code.
The final step varies depending upon whether your app must support iOS 4.3.

If your application supports iOS 4.3 you must include the CFBundleIconFiles key to specify your application's icon images. The value for this key is an array of strings, each identifying an image in the bundle. If you have included images for the iPad-specific icons, you may either list them under the CFBundleIconFiles key, or you can list them under the device specific CFBundleIconFiles~ipad key. iPad-only applications should list their icon images under the CFBundleIconFiles key.

Listing 1 Example configuration for a universal app with deployment target of iOS 4.3.

<key>CFBundleIconFiles</key>

<array>

    <string>Icon-Small</string>

    <string>Icon-Small-40</string>

    <string>Icon-Small-50</string>

    <string>Icon</string>

    <string>Icon-60</string>

    <string>Icon-72</string>

</array>

<key>CFBundleIconFiles~ipad</key>

<array>

    <string>Icon-Small</string>

    <string>Icon-Small-40</string>

    <string>Icon-Small-50</string>

    <string>Icon-72</string>

    <string>Icon-76</string>

</array>

If your application supports iOS 5.0 or above, you should include the CFBundleIcons key to specify your application's icon images. The value for this key is a dictionary with two child keys: CFBundlePrimaryIcon and UINewsstandIcon. The UINewsstandIcon key is for newsstand apps and can otherwise be omitted. The value for the CFBundlePrimaryIcon key is a dictionary that identifies the icon images associated with the app bundle. It may contain two child keys: CFBundleIconFiles and UIPrerenderedIcon. The value for the UIPrerenderedIcon key is a boolean that specifies whether your icon files already incorporates a shine effect. The value for CFBundleIconFiles key is an array of strings, each identifying an image in the bundle.

Listing 2 Example configuration for a universal app with deployment target of iOS 5.0 or greater.

<key>CFBundleIcons</key>

<dict>

    <key>CFBundlePrimaryIcon</key>

    <dict>

        <key>CFBundleIconFiles</key>

        <array>

            <string>Icon-Small</string>

            <string>Icon-Small-40</string>

            <string>Icon-Small-50</string>

            <string>Icon</string>

            <string>Icon-60</string>

            <string>Icon-72</string>

        </array>

    </dict>

</dict>

<key>CFBundleIcons~ipad</key>

<dict>

    <key>CFBundlePrimaryIcon</key>

    <dict>

        <key>CFBundleIconFiles</key>

        <array>

            <string>Icon-Small</string>

            <string>Icon-Small-40</string>

            <string>Icon-Small-50</string>

            <string>Icon-72</string>

            <string>Icon-76</string>

        </array>

    </dict>

</dict>

Important: When specifying the name of each image, it is best to omit any extensions. Omitting the extension lets the system automatically detect high-resolution (@2x or @3x) variants of your image files using the standard-resolution image filename. If you include extensions, you must specify all image files (including the high-resolution variants) explicitly.

Troubleshooting

This section describes common problems and how to fix them.

Note: Before attempting further troubleshooting, perform a clean build of your application (Hold down the Option key and choose Product > Clean Build Folder, then Product > Build from the Xcode menu bar) and remove the app from your test device or simulator. Build your app again and attempt to reproduce the problem. You may also try clearing the contents of Xcode's derived data folder (~/Library/Developer/Xcode/DerivedData/) before building again.

My application fails to validate

There are multiple icon-related problems that will result in your application failing validation by Xcode or iTunes Connect. The underlying issue depends upon the error.

Error: Invalid Image Path

Your application's information property list references one or more icon images that were not included in the compiled bundle.

If your application is using asset catalogs to manage its icons then the information property list should not include any icon related keys; they will be added at build time by the asset catalog compiler.

Open the information property list for your app's target. It can be found under the Info tab in the project editor or in the File Navigator where it will be named either <ProductName>-Info.plist or Info.plist, where <ProductName> is the name of your app.
Remove the following keys, including device specific variations.
- “Icon file” (CFBundleIconFile)
- “Icon files” (CFBundleIconFiles)
- CFBundleIcons

If your application is not using asset catalogs to manage its icons, one or more of the images listed under the CFBundleIconFiles key or the CFBundleIcons key in the information property list is not associated as a resource of your application, may not have been added to your project, or may have been accidentally removed from your project. Verify that all the images named by either of these keys is included in your project then follow the resolution steps listed under My icons don't appear on the device to verify that it is associated with your application.

Error: Missing required icon file

Your have not included artwork for one or more of the required icons, based on your app's supported devices and deployment target.

Refer to the tables above for the list of required icons. Verify that each of your icon images matches the size listed in the table.

If your application is not using asset catalogs to manage its icons, verify that all of your icon images are listed under the CFBundleIconFiles key or the CFBundleIcons key as described in Configuring Icons Without an Asset Catalog. Remember that if you include filename extensions in the Information Property List, you must specify all image files (including the high-resolution variants) explicitly.

My icons don't appear on the device

If your project is using asset catalogs, your application may not be configured to use the correct icon set.

Select the name of the project in the project navigator.
Select the name of a target from the list in the left column of the project editor.
Select the General tab at the top of the project editor.
Verify that the name of the app icon set is selected in the Source menu under the App Icons section, as shown in Figure 5.

Figure 5 The Source menu controls which icon set is used as the app icon set.

If your project is not using asset catalogs to manage its icons, one or more of your icon images may not be associated with your app's target.

Select each of your icon images in the project navigator.
In the utility panel, check the box next to your app's target under the Target Membership pane as shown in Figure 6.

Figure 6 Associating an icon with a build target

Verify that your icon images use a supported color model. Images that do not use the RGB color model may appear correctly in Xcode but will fail to load on the device. If your icons include transparent areas, use your preferred graphics editing software to fill these areas with a solid color.

Some graphics software may produce images which load correctly in Xcode but fail to load on the device, resulting in a blank icon. Try exporting your icon images with a different graphics editor such as the built in Preview app.

A previous version of my icon appears on the device

Your testing device or simulator may have a partially outdated build. That is, Xcode failed to copy a modified resource to the app bundle it installed on the device as part of the build & run process. To force Xcode to copy the most recent resources from your project directory:

Remove the app from your testing device or simulator.
Clean the build directory. Hold down the Option key and choose Product > Clean Build Folder, then Product > Build from the Xcode menu bar
Build and run your app.

If your project is using asset catalogs then you must replace the modified image in the asset catalog. Asset catalogs do not track files on disk, opting instead to make a copy of the image at the time it is added to the asset catalog.

My icon has a black background in the App Store

The Large App Icon you uploaded to iTunes Connect includes transparent areas. The iTunes Connect Developer Guide lists the complete requirements for the Large App Icon, including that it must be opaque.

You can use the Preview app to check your image for transparent areas, which will appear dark grey as shown in Figure 7. Use your preferred graphics editing software to fill in the transparent areas with the desired background color.

Figure 7 Preview's dark grey canvas background is visible through transparent areas in an image.

The wrong icon appears in the App Store

Your application bundle includes additional images which are being detected as valid icon images.

Note: Different icon images from the application's bundle, and the large app icon, are displayed in various contexts within the App Store. For example, the incorrect icon image may appear in the search results but not on your application's landing page.

You may encounter this issue if your icon images deviate from the naming convention shown in the above tables. If your application bundle also contains once or more images that match the naming convention in the tables above, these images may be detected as valid icon images by the App Store. This may occur regardless of whether those images are included in the asset catalog or are referenced by the application's Information Property List. The solution is to rename or remove the images.

You may encounter this issue when building an app using a third party development environment or if your project was created using a template project provided by a third party. Both will usually include a default set of icon images. If you fail to remove these images or replace all of them with your own artwork, the App Store may display them in the search results for your app. Like the iOS home screen, the icons displayed in the search results depend upon the current device. It is possible that the incorrect icon is shown in the search results on certain devices but not others.

The solution is to delete any instances of the template-provided icons that remain in your project and remove any references to the deleted files from the information property list. Due to the wide variety of ways in which iOS versions have allowed developers to specify app icons in the Information Property List, you may find it simpler and less error prone to remove all icon related keys from the Information Property List and then reconfigure your app's icons using the steps presented in Adding Icons to Your App. See Start Over.

Start Over

If the none of the above solutions resolve the problem, follow the steps below to remove all the icons and icon related configuration from your app. Then follow the steps in Adding Icons to Your Appto re-configure the proper icons for your app.

Warning: Make sure you have a backup of your icon artwork at a location outside of your project directory.

Remove the Icon Set From Your Asset Catalog

Select the asset catalog in the project navigator. It is named Images.xcassets by default.
In the left column of the editor, control click the icon set and choose Remove Selected Items from the context menu. By default the icon set will be named 'AppIcon'.

Remove Icon Images From Your Project

Using the Xcode file navigator, remove any icon images from your project your had previously added to your project as resources. Icon images usually have a file name beginning with 'Icon' or 'AppIcon'.

Remove Icon Related Keys From The Information Property List

Open the Information Property List for your application. It can be found under the Info tab in the project editor or in the navigator where it will be named either YourApp-Info.plist or Info.plist.
Remove the following keys, including device specific variations.
- “Icon file” (CFBundleIconFile)
- “Icon files” (CFBundleIconFiles)
- CFBundleIcons

Clean The Project

To remove any cached icons, clean your target. Choose Product > Clean from the menu bar.

Finally, follow the steps in Adding Icons to Your App to re-configure the proper icons for your app.

Additional Resources

For additional information, see the App Icons section in the iOS App Programming Guide.

For information about designing your application's icons, see the App Icon section of the iOS Human Interface Guidelines.

For an example project with properly configured icons, see the Application Icons and Launch Images for iOS sample code.

Document Revision History

Date	Notes
2014-12-01	Added iPhone 6 Plus icons. Further expanded the troubleshooting section.
	Added iPhone 6 Plus icons. Further expanded the troubleshooting section.
	Added iPhone 6 Plus icons. Further expanded the troubleshooting section.
2014-05-19	Added troubleshooting steps for incorrect icons appearing in the App Store search results.
2014-02-03	Updated for Xcode 5 and iOS 7.
2013-07-18	Added icon information for iPad with retina display.
2011-07-14	After iOS 4.3, order doesn't matter in the icon arrangement. Added links to related references.
2010-07-14	Fixed outdated "Add Icon files in Info.plist" section.
2010-07-12	Updated for iOS 4 requirements.
2010-04-09	New document that explains how the icon files in an application bundle are used on iPad and iPhone.

Launch Images

A launch file or image provides a simple placeholder image that iOS displays when your app starts up. The placeholder image gives users the impression that your app is fast and responsive because it appears instantly and is quickly replaced by the first screen of your app. Every app must supply a launch file or at least one static image.

In iOS 8 and later, you can create a XIB or storyboard file instead of a static launch image. When you create a launch file in Interface Builder, you use size classes to define different layouts for different display environments and you use Auto Layout to make minor adjustments. Using size classes and Auto Layout means that you can create a single launch file that looks good on all devices and display environments. (For an overview of display environments and size classes, see Build In Adaptivity; to learn how to use size classes in Interface Builder, see Size Classes Design Help.)

If you also need to support earlier versions of iOS, you can continue to supply static launch images in addition to a launch file.

IMPORTANT

You use a launch XIB or storyboard file to indicate that your app runs on iPhone 6 Plus or iPhone 6.

The following design guidelines apply to both launch files and static launch images.

Design a plain launch image that improves the user experience. In particular, the launch image isn’t an opportunity to provide:

An “app entry experience,” such as a splash screen
An About window
Branding elements, unless they are a static part of your app’s first screen

Because users are likely to switch among apps frequently, you should make every effort to cut launch time to a minimum, and you should design a launch image that downplays the experience rather than drawing attention to it.

Design a launch image that is identical to the first screen of the app, except for:

Text. The launch image is static, so any text you display in it won’t be localized.
UI elements that might change. If you include elements that might look different when the app finishes launching, users can experience an unpleasant flash between the launch image and the first app screen.

If you think that following these guidelines will result in a plain, boring launch image, you’re right. Remember, the launch image doesn’t provide you with an opportunity for artistic expression. It’s solely intended to enhance the user’s perception of your app as quick to launch and immediately ready for use. For example, Settings and Weather each supply a launch image that is little more than a background image.

The Settings launch image

The Weather launch image

If you need to use static launch images, you create images in different sizes for different devices. Static launch images for all devices must include the status bar region. For specific measurements, see Table 41-1.

Although it’s best to use a launch file for iPhone 6 and iPhone 6 Plus, you can instead supply static launch images if necessary. If you need to create static launch images for these devices, use the following sizes:

For iPhone 6:

750 x 1334 (@2x) for portrait
1334 x 750 (@2x) for landscape

For iPhone 6 Plus:

1242 x 2208 (@3x) for portrait
2208 x 1242 (@3x) for landscape

If you’re using static launch images, you can give each image a name that specifies how it should be used. The format of the launch image filename includes modifiers you use to specify the device, resolution, and orientation of the image. To learn how to name launch images appropriately, see App Launch (Default) Imagesin App Programming Guide for iOS.

Icon和LunchImage