Duo Mono

"Duo Mono" is an Android app that allows Surface Duo users to easily turn off one screen while in unfolded mode. This functionality is perfect for simplifying your experience, making it feel like a single-screen device. You can launch the app from the desired screen to turn it off, and navigate seamlessly. Although the navigation bar remains visible, it can be hidden for uninterrupted viewing. A Quick Settings switch provides easy access for toggling the screens. Note that it doesn’t require any permissions and hasn't been tested on Surface Duo 2.