Foldable iPhone launches in France

Apple's iPhone Duo, the company's first foldable smartphone, has begun its market debut, with initial reports highlighting both challenges and successes in app compatibility. The device features a large internal screen, raising questions about how iOS applications adapt to this new form factor.

App compatibility issues persist

According to one report, Apple envisions apps displaying their buttons on the right edge of the screen, but several apps still show an unsightly black bar in this area due to not having been updated. Apple has planned three levels of compatibility for apps, depending on the SDK used to compile them.

Developer timeline was tight

Apps compiled with an SDK prior to iOS 27 maintain their original size with black bars on the sides. Those using the iOS 27 SDK are partially adapted, while apps requiring the iOS 27.1 SDK can fully utilize the large screen. Developers had limited time to prepare, as Apple released the first beta of Xcode 27.1, the tool for optimizing apps for the Duo, only on September 18.

Netflix adapts well to the Duo

Netflix has been cited as an example of an app that has adapted well to the iPhone Duo. The app stretches its interface across the entire width of the screen horizontally, with main shortcuts grouped in a side bar. When switching to vertical mode, these buttons logically move into a bar at the bottom of the screen, similar to a classic iPhone.

Duo’s unique features and bugs

The lower half also displays real-time colorful reflections calculated from the video content, a feature inspired by Philips' Ambilight on TVs. This decorative element avoids a large black rectangle in front of the user. However, some minor bugs were reported, including instances where the exit button for a video did not respond and a side bar displaying empty icons, which was resolved by changing the device's orientation twice.

iPhone Duo now available in France

The iPhone Duo is available in stores in France starting on October 23, with a starting price of 2,339 euros for the 256 GB storage version.