iOS has many useful and interesting features, but when it comes to app icons, the system is quite rigid. While Apple allows app developers to use a feature called Alternate App Icons to add one or more app icons that users can switch between, these changes can only be added manually by the user, eliminating the ability for developers to include interactive or animated icons. However, a developer found an iOS exploit that bypasses these restrictions to add animation to app icons.
Exploiting an animated app icon for iOS: How it works
As researcher Bryce Bostwick explained in a blog post, this iOS exploit solves two key problems. First, iOS sends an alert to the user every time an app icon changes. Second, the alternate app icons feature doesn’t work in the background, which means the effect can’t be implemented if the app isn’t active. This is pointless because if the app is active, the user can’t see the icon anyway.
Bostwick illustrates two solutions to circumvent these limitations. To override the alert system, the researcher uses a private call to the iOS programming interface (API). This is a simple fix that requires minor changes to the API code, as illustrated in the YouTube video. The second change requires extensive fixes and changes to the application’s UI state.
By completing both steps, Bostwick showed that it is indeed possible to add multiple app icons and then alternate between them so quickly that it gives the impression of animation. In fact, developers should not try this because Apple will probably review the changes and reject them immediately.
Animated app icons on iOS are purely cosmetic
While it’s an odd feature that would make sense for some apps (Apple already allows dynamic icons for its Clock and Calendar apps), for most third-party apps it would just be a gimmick for fun. In addition, there is a potential for abuse as developers can use fake tricks to attract users’ attention to the application.
There are also technical problems. To change app icons quickly enough, the app should run in the background, which can result in faster battery drain. The animation of the application icon itself can further drain the battery. Apple likely restricts this action for these reasons and will likely patch the exploit that enables this functionality.
However, according to the report, Apple plans to offer some app icon customizations to users with iOS 18. The company may allow users to recolor the app icon and place icons anywhere on the home screen, ditching its standard grid pattern.
