Apple released Xcode 27.1 with Swift 6.4 and the iOS 27.1 SDK on October 15, and App Store Connect began accepting applications built with it. Running Xcode requires macOS Tahoe 26.6 or later. Alternate-display previews for iPhone Duo were added, but the simulator does not support StandBy or running and debugging most app extensions. Mac Catalyst builds using iOS 27.1-only APIs need measures such as conditional compilation, and camera behavior across both displays should also be checked on real hardware.