on iOS → after a lot of testing and consideration, I use Editorial app. it has the basics to get you started. I wrote an app on top of it to make it more usable with Taskpaper, but you don’t need all that
in the web → no good solution right now, but this person was working on a web version
on windows → idk i dont use windows. but if there was a web version you could make a windows version easily by wrapping it in an app
ai → its a custom app I built for my machine. you’d have to host a server and other very technical things