Apple today announced that apps optimized for the iPhone Duo can now be submitted for App Store approval, ahead of the foldable device’s launch on Friday, October 23.
Existing App Store apps will automatically run on the iPhone Duo, but only apps built with the iOS 27.1 SDK or later can dynamically resize to fill the device’s inner display; unoptimized apps will appear with black borders.
Developers can prepare their apps using Xcode 27.1, and Apple has published tips on its website to help developers optimize for the new device.
Preparing apps for iPhone Duo
Apple states that developers should build with the iOS 27.1 SDK or later and use Xcode 27.1 to enable dynamic resizing and full use of the inner display. Apple has shared guidance on its website to assist with these updates and developers may submit optimized apps for App Store review now.
