So I'd like to enable screen auto-rotation for YouTube and Chrome, but not for other anything else. How do I do this?
I use a Galaxy S5.
Have you tried a 3rd-party app like Smart Rotator?
Are you tired of switching auto-rotate setting back and forth? This tool can help you auto switching it.
You can set auto-rorate/portrait/landscape setting for each app, when you open those apps, it will help you set screen orientation to auto, portrait, landscape automatically.