Apple's iPhone Duo Simulator Ships Without StandBy or Extension Debugging

Apple releases iPhone Duo simulator and Xcode 27.1 beta

Xcode 27.1 beta bundles Swift 6.4 and SDKs for iOS 27.1, iPadOS 27.1, tvOS 27, watchOS 27, macOS 27, and visionOS 27, and requires a Mac on macOS Tahoe 26.6 or later. Developers testing the new iPhone Duo Simulator runtime will find StandBy and most app extension debugging unavailable, while Mac Catalyst builds hit compile errors on iOS 27.1 APIs.