
After initial testing of iOS 15, which revealed that many third-party apps
Apple says developers will need toadd a new Info.plist key to make the function work, and documentation on this is coming soon. Additionally, an upcoming software update will address a bug that prevented Core Animation-driven animations from reaching their maximum refresh rate of 120Hz.
Standard animations and interactionsScrolling behavior is automatically improved using ProMotion without the need for developers to write custom code. This functionality includes power savings at times when the screen can throttle down to 10Hz rather than just peak at a smooth 120Hz.
For battery saving reasons,apps will have to drop 120Hz support if they do custom user renderingfor example in games. A complete list of steps that developers need to follow will be officially documented shortly.
Source: 9to5mac
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