100,000 iPhone Duo apps sounds big, but support is uneven

What Apple announced

Apple has announced that more than 100,000 apps have been built or updated for the iPhone Duo, its first foldable iPhone, just weeks after the device went on sale. The figure was highlighted in an Apple press release and reported by Apple Insider on 13 November 2026.

The number sounds impressive at first glance. Apple Insider argues, however, that it does not tell the whole story, because a far larger group of apps has not been rebuilt to take advantage of the foldable form factor.

Three tiers of app support

According to Apple Insider, apps on the iPhone Duo fall into three groups. The best group, which includes the 100,000 apps Apple highlighted, fills both the inner and outer displays edge to edge. These apps also use adaptive vertical navigation bars, moving controls that would normally sit at the bottom of the screen to the side, within thumb reach, and they work properly with Apple's Split View multitasking.

The middle group resizes to fill most of the inner display but lacks the vertical navigation controls. On the outer display, the app leaves a black vertical bar where the status bar sits, so the full width is not used. These apps are usable but not polished.

The worst group treats the iPhone Duo like an older device. On the outer display the app looks like a normal iPhone app, but when the phone is opened it appears as a small window in the middle of the large inner display, surrounded by black borders. Apple Insider compares this to running old iPhone apps on an iPad.

Why the differences exist

The split comes down to which software development kit, or SDK, an app was built with. Apple released the first Xcode 27.1 beta with iPhone Duo support on 18 September 2026, about a month before the device went on sale. Apps built against the iOS 27.1 SDK are the ones that make full use of the hardware and account for the 100,000 figure.

Apps built against the older iOS 27 SDK form the middle group. Apple Insider notes that these are still a big improvement over apps built with pre-iOS 27 SDKs, which have no awareness of the foldable display at all.

Historically, apps rebuilt quickly for new Apple hardware tend to come from independent developers, though some large companies updated their apps before the iPhone Duo launched.

Big-name apps left behind

Apple Insider reports that several well-known apps still fall into the worst category, including the PlayStation, Xbox and Nintendo apps. Football Manager 27, a new title promoted in a recent Apple Arcade press release, also lacks iPhone Duo support.

The report also cites the NHS app in the UK as an example of a widely used service that has not been updated. Apple Insider suggests such apps may stay that way for a long time, because the organisations behind them have little incentive to act quickly.

The iPhone Duo's relatively small user base, compared with the rest of the iPhone lineup, is one reason large companies may not prioritise the work.

Why it matters

Apple Insider warns that if developers settle for the middle ground of merely filling the display, the iPhone Duo could repeat the pattern of the Apple Vision Pro. Apps built for older devices run on the headset, but they do not make the most of what the hardware offers.

The report argues that full support, with reworked navigation and proper use of both displays, should be the benchmark rather than the exception. Whether that happens depends largely on developers, and Apple Insider suggests there is no guarantee it will happen soon.

For buyers of the foldable iPhone, the practical advice is to check how their favourite apps behave on the inner display, since the experience varies widely between the three tiers.