net user
obs, flameshot/sharex, and 7-zip
also, the sponsorblock addon works on mobile and there is an addon that allows videos to play in the background if you need that. i haven’t tested this with youtube music in the browser but i wouldn’t be surprised if it also worked.
pipepipe and rimusic is what i use. youtube in the browser is fine too, if you disable that “open in the youtube app” popup (firefox for android with ublock origin addon is what i use, although i have experienced some regressions with the ad-blocker not working after youtube updates something, but ublock is usually on top of it and fixes stuff quickly).
also syncthing, if you’d like to synchronize a directory to act like a shared folder and be identical on both devices
nixcon north america was sponsored by anduril https://nixos-users-against-mic-sponsorship.github.io/
It would be great if Plasma gets a kiosk mode option some day, that seems right up KDE’s alley as far as the “simple by default, powerful when needed” philosophy goes.