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App Icons

Your app's icon is what users see on the home screen of their devices, as well as in the App Store and Play Store. This is one topic where platform differences matter, and requirements can be strict. This guide offers details on how to make sure your App Icon looks as good as possible on all devices.

The most straightforward way to provide an icon for your app is to provide the icon key in app.json. If you want to do the minimum possible, this key alone is sufficient. However, Expo also accepts platform-specific keys under ios.icon and android.icon. If either of these exist, they will take priority over the base icon key on their respective platform. Further customization of the Android icon is possible using the android.adaptiveIcon key, which will override both of the previously mentioned settings. Most production-quality apps will probably want to provide something slightly different between iOS and Android.

  • The icon you use for iOS should follow the Apple Human Interface Guidelines for iOS Icons.
  • Use a png file.
  • 1024x1024 is a good size. The Expo build service will generate the other sizes for you. The largest size it generates is 1024x1024.
  • The icon must be exactly square, i.e. a 1023x1024 icon is not valid.
  • Make sure the icon fills the whole square, with no rounded corners or other transparent pixels. The operating system will mask your icon when appropriate.

  • The Android Adaptive Icon is formed from two separate layers -- a foreground image and a background color or image. This allows the OS to mask the icon into different shapes and also support visual effects.
  • The design you provide should follow the Android Adaptive Icon Guidelines for launcher icons.
  • Use png files.
  • The default background color is white; to specify a different background color, use the android.adaptiveIcon.backgroundColor field. You can instead specify a background image using the android.adaptiveIcon.backgroundImage field; ensure that it has the same dimensions as your foreground image.
  • You may also want to provide a separate icon for older Android devices that do not support Adaptive Icons; you can do so with the android.icon field. This single icon would probably be a combination of your foreground and background layers.
  • You may still want to follow some of the Apple best practices to ensure your icon looks professional, such as testing your icon on different wallpapers, and avoiding text besides your product's wordmark.
  • Provide something that's at least 512x512 pixels. Since you already need 1024x1024 for iOS, it won't hurt to just provide that here as well.

  • If your app contains privacy: public in app.json, it will show up on your expo.io profile. We will mask your icon to have rounded corners in that circumstance, so if it already looks reasonable on iOS, it will probably look good here as well.