Mirroring that scales
macOS 27 Golden Gate's iPhone Mirroring improvements go beyond the wireless reliability fix highlighted at the keynote: early analysis of the developer betas reveals that iPhone app windows can be freely resized on the Mac desktop. When the user expands a window past a certain threshold, many apps automatically abandon the compact iPhone layout and adopt the iPad interface — with sidebars, dual-column panels, and adaptive controls.
As Thurrott reports citing direct developer tests, the behavior works correctly on most apps updated for iOS 27 — including third-party apps recompiled without code changes. Not all apps support it in this first beta, but the direction is clear.
Why it matters
Until now, iPhone Mirroring was mainly useful for checking notifications or using apps absent on Mac. With resizing and the iPad layout, it becomes a genuine second screen for mobile apps, bringing macOS closer to an ecosystem where iPhone, iPad, and Mac share visual space fluidly. It's also an indirect signal of Apple unifying multiplatform layout APIs — work that will prove equally useful for the upcoming foldable iPhone.