Yeah, I think a cron job to move/rsync is the most robust method.
if i sync deletes from the backup device to the phone then a cron job to move files would potentially cause files to be removed from the phone before i am done with them.
rsync would cause the files to be duplicated (although i could still hardlink using rsync)
ah for rsync I meant with --remove-source-files flag -- it's just sometimes rsync is easier to use than move, depending on the hierarchy of your files
unles you mean to sync first, then move files i want to keep on the backup only out of the way and rsync --remove-source-files those files again.
the problem with that is that when i do remove files on the phone, then it's because i need the space. at which point i don't want to wait.
syncthing does what i want. that is not the problem. them problem is only that it is easy to forget to set up ignore-delete, and that it's hard to monitor the sync status of the backup from the phone.
i appreciate the suggestions, but they don't really do much to help my case. what is really needed is an improvement of the syncthing UI and in particular a redesign of the way the status is handled.
for my backup maybe i'll set up an rsync with hard-links to create a second version of all files which protects them from accidental deletion.