The structure of the notebooks is not transferred when synchronising from Windows to Adroid via Dropbox. The notes all end up in the main folder of my adroid app.
Not all notes, folders, or tags are displayed on the mobile app
Joplin does not have a background sync on mobile devices. When Joplin is closed, sent to the background or the device is put into sleep (display off), the sync is interrupted.
Unfortunately, this has nothing to do with the background sync.
The notebook structure is not transferred at all. Only the notes within the notebooks are transferred.
After installation the Joplin app on my Android mobile phone does not initially contain any notes.
Then I synchronise with the Windows app via Dropbox. There are about 3000 notes there, organised in about 50 notebooks.
As I said, the notes all arrive on the mobile phone, but the structure of the notebooks is lost. All messages end up in a large "bag".
Search here for recent Dropbox topics. Apparently they changed something server-side, and synchronization isn't working as well. There was a topic where a Dropbox user, with issues,moved to Onedrive and their sync problems went away.
If you pay for Dropbox, probably worth a support case.
Thanks for your hint.
I tried WebDav before, but the notebook structure did not arrive there either.
I will try OneDrive. But I don't have much hope. It seems to me to be something more fundamental.