Apple's iPhone Duo Software Bet Hinges on Developer Rebuilds

The 9to5Mac report says Apple could have allowed resizable iPad binaries to run on the iPhone Duo. That path would have offered broader compatibility, but the report says it would likely feel more janky. It also would likely have taken developers longer to support the iPhone Duo's interface elements if a compatibility layer existed. Apple chose not to do that, the report says, because the interface designed for the iPhone Duo is intuitive and makes the product feel carefully considered. Supporting resizable iPad apps would make the Duo feel more like other Android foldables.

The report points to another hurdle: compiling for iOS 27 also means developers no longer have the compatibility option to opt out of supporting Liquid Glass. For developers who have not prepared, that requirement may cause many to drag their feet on iPhone Duo updates. Split screen on the Duo could soften the impact of apps that do not fully expand on the inner display, but only if Apple supports split screen with non-native apps.

Mobile gaming is described as a use case likely to be popular on the iPhone Duo's inner screen. Without a proper full-screen experience, the report says, many users could be deterred. The report expresses hope that Apple's efforts to encourage developers to support the Duo's interface will work, while also voicing genuine worry. The outcome will become clearer over time.

In a worst-case scenario, 9to5Mac suggests Apple could add an iPad app compatibility mode to the iPhone Duo in iOS 28. That would improve the experience for users while the initial wave of support develops. The report says it is excited about the iPhone Duo, but warns that Apple's gamble on getting third-party developers to support Liquid Glass and the Duo at the same time could cause a rough experience in the first few months.