As I have written elsewhere, BeNice allows one to create PAIRS of apps side-by-side.
Launch any app in split-screen mode
play.google.com
As in the attached image, you can see a NotePad app side-by-side with The NY Times Wordle game. Where I was working with potential solutions to the puzzle in the Notepad. It is not perfect and depending on the app, you may have to step through an app to show what you want. For instance, I have a personal weather station and can display stats. I opened it side-by-side with Accuweather. But I have to step through Accuwather to get to the radar map of the area. I would imagine using Tasker or similar one could help automate that aspect of the process.
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