check out termux if you have an android. not sure is the ios terminals let you do as much. its pretty neat being able to run yt-dlp to download the odd youtube video or ffmpeg to resize photos or videos before sending them off. i have all my python and lua scripts synced with syncthing and they all work as normal. fzf gets quite a bit of use in my scripts, like searching tmdb for a movie, showing the results in an fzf menu, then adding it to a watchlist. i have another one that lists all my spotify playlists in fzf then opens the playlist in the android app. its kind of crazy how much you can do with it. i even started learning neovim a few months back just so i could edit the scripts easier on my phone and im surprised how much easier it is to use on mobile compared to other android IDEs.

the only other thing that comes to mind is streetcomplete which asks you questions about the openstreetmap map in your area. its a nice casual way to contribute to osm without having to do anything too complicated