I would like to setup a private cloud service on my NAS (Synology) that I can use for the double purpose of syncing files with my mobile devices AND backuping (safely) those files.
I first was thinking using Nextcloud but I could not find there how to backup my data: files are perfectly synchronized but if I delete a file from my mobile device, it will also be deleted from my NAS data folder. I think this is fine for some usages, but it’s not what I need. After a file is saved in my NAS data folder, I would like to be free deleting it from my mobile device without deleting from the storage (NAS data folder).
With Nextcloud I could not find rules for synchronization (one way only, 2 ways), it seems to be fixed.
Final purpose is quite simple: I want to save my data from my phone to my NAS in background (sync) and free some space on my phone by deleting files on the phone only and being able to browse from my phones files stored in the NAS even they are not on the phone anymore.
Last requirement here: I want to avoid as much as possible Synology cloud / backup solutions as I already had issues with their backup tools.
Is Nextcloud a suitable solution for this purpose ? Or any other personal cloud can help ? Or is the approach not good here ?