What researcher @M1Astra found
Hours after the iOS 27 developer beta was published, researcher @M1Astra found unambiguous references to a foldable device in the code: strings like "foldState" and "angleDegrees" and other identifiers describing the physical states of a device with a hinge. TechCrunch reported the finding, noting that "Apple didn't make such a big reveal during WWDC," but that the beta code contains "references to things like 'foldState,' 'angleDegrees,' and other things that allude to the states a foldable device can be put into."
The distinction from already-published slugs
The site has already covered the public developer APIs (ios-27-foldable-iphone-layout-api-hinge-state-swiftui), which concern officially documented interfaces from Apple. These beta references are different: they are undocumented internal code, likely related to system-level testing for the physical foldable hardware, not just layout APIs for third-party developers.
September is approaching
The combination of evidence — public layout APIs, hinge-state optimizations in SwiftUI, and now these system-level references — forms a coherent picture: iOS 27 is built knowing that September will bring hardware with a radically different form factor. Apple didn't say it on stage, but it wrote it in the code.