Apple’s iPhone Duo hit stores today, and the App Store will now label apps that are “Made for iPhone Duo.” Apple made that announcement in its press release highlighting apps that have been optimized for the iPhone Duo,
To optimize their apps for the iPhone Duo, developers are require to build it with the iOS 27.1 SDK or later. Apps optimized for the iPhone Duo will fill the entire inner display, with the app’s toolbar appearing vertically below the status bar.
While apps built with the iOS 26 SDK or earlier will run on iPhone Duo, they won’t adapt to all layouts. When the device is open, the app will appear in the center of the display, with empty space surrounding the window. When the device is closed, the outer display will show the app’s content to the left of the status bar and camera.
Apps built with the iOS 27 SDK resize to fill most of the inner display on iPhone Duo, but still avoid the status bar on the right edge. This provides an improved experience, as empty space is minimized.
Apps built with the iOS 27.1 SDK or later are optimized for iPhone Duo. Apps will extend to use the full display, with toolbars and tab bars appearing vertically below the status bar. This provides users with an optimal and consistent experience as they move across displays.
Apple advises developers that before shipping an app build with the iOS 27.1 SDK, make sure their app’s content adapts to the bars becoming vertical.
We can expect more an more iPhone app sbeing optimized for the iPhone Dup in the coming days, so keep an eye out for updates for your favorite apps.