Comment by CharlesW

> It'll be interesting to see how many/how quickly apps adopt the UI that lets you make the most of the foldable screen.

For iOS 27, apps are automatically automatically opted in to resizability. Apple was clear at WWDC that apps need to dynamically adjust to any available scene size at runtime, not just for iPhone Duo, but also for iPad windowing and iPhone Mirroring on Mac. There may be a grace period, but Apple hasn't shared one AFAIK.