Great thread!
I stumbled up this today so I figured I would share it here as it can sync using nextcloud and that could prove useful for Cloudron users. You are able to format and view notes differently than joplin. I was impressed with Joplin's web clipper. Joplin's biggest asset is it has a huge following. There are alot of plugins being developed to broaden what you can do with it.
https://opentodolist.rpdev.net/
https://gitlab.com/rpdev/opentodolist
"A todo and task managing application, written in Qt and using QML for its UI. OpenTodoList is targeted at typical desktop environments (Windows, Linux, Mac OS X) as well as mobile devices such as Android phones."
This is a nice video walk through.
It looks like select whether each notwork is local or not. I am not sure if you can do that with joplin. Here is a link to the android app.