I understand two key concepts from desktop platforms:
Screen Mirroring – The same content is displayed on both the primary and external screens.
Screen Extension – The external display shows different content that complements what's on the main screen.
My question pertains to the second point: Is it possible to extend the display on iOS and iPadOS devices?
I'm referring to this Apple documentation, which explains how to extend content from an iOS/iPadOS device to an external display.
I tested this in a sample iOS Xcode project. In the iOS Simulator, I was able to detect an "external display" and present a separate UIWindow on it. However, when I tried the same on a real device (iPhone 15 connected to a MacBook Pro via cable), the external display connection was not detected.
I’d like to confirm whether screen extension is possible on a real iOS device. From my research, it appears that extension is only supported on iPadOS via Stage Manager, but I want to verify if there’s any way to achieve this on an iPhone. If so, are there any known apps that currently utilize extended display functionality on iOS?
If extension is not possible on iOS, what does the documentation mentions iOS?