In article , R.Wieser
wrote:

That requires some kind of central "server".
...
Perhaps that's the native SMB server inherent in Windows?
...
Or perhaps that's some other server, e.g., ftp, or http?

You already have ideas, go google them ! You might even find some other
possibilities too (in other words: do not expect us to do your work for
you).

And by the way: good luck with finding something that runs iOS that will
talk SMB. And there is a good chance it will not even run FTP nativily
either.

there are numerous ftp and smb apps for ios, either server or client,
as well as many other protocols.

where he needs luck is in getting his convoluted method to work
anywhere near as well as an existing password manager, or as secure.