NVIDIA SHIELD Has A Hidden Split Screen Mode
NVIDIA is the company that just keeps giving, at least as far as Android gamers and users are concerned. Long past the usual two-year support period, NVIDIA continues to push updates to its SHIELD Android TV box with new games, apps, and features. Granted, this latest one isn't exactly something that NVIDIA has directly given SHIELD owners but if this split screen mode is really a feature rather than a bug, the users will probably consider it as one anyway.
Android itself has actually had split screen support for quite a while. It was officially made available start Android 7.0 Nougat in 2016 but the platform itself could technically support it even before that. Given Android TV's immersive experience, however, you probably don't expect it to support such a mode.
User Thobal over at NVIDIA's GeForce forums stumbled on the "feature" by accident when he pressed the Cmd (Win) key and "^" (caret) key that sent the current app to the left half of the screen. It turns out that Cmd/Win + "$" (dollar sign) send it to the opposite side. Others have later confirmed this and also added that using square brackets ("[" and "]") perform similar functions.
What is perhaps more interesting is that, as the video above shows, both apps continue to run regardless of which one has the current input focus. This implies this is a proper Android implementation, otherwise YouTube would have paused if it lost focus.
Most smart TVs these days resort to picture-in-picture functionality to display two screens or apps at the same time, something Android TV also has. A split screen, however, could prove to be more useful in some cases. Hopefully, it isn't a bug that NVIDIA just accidentally exposed and will remove in a future update.