The phone and the desktop app keep a copy of every note, so they
open, edit, create, record and search with no connection at all.
What you do offline waits on the device and is sent, in order,
the next time the server answers. Each new note and upload
carries its own id, so one whose reply was lost is
never applied twice.
Every save names the version of the note it was made on. If the
note has changed since, on another device or by someone you
share the folder with, the save is refused and the app asks you:
keep mine, or take theirs. A newer version is
never silently overwritten.