I have a VPS server in the cloud that I use for wireguard. I got the idea to also use it to host a shared folder across my devices: Linux laptop and Android phone.
I started doing some research on this, and would welcome pointers.
Syncthing. I switched from Dropbox to syncthing several years ago when Dropbox started enshitifying and never looked back.
you could do that via SFTP, Samba, NFS or iSCSI.
I’ve been using self-hosted Seafile for quite a while and can recommend it.
I would not “share” it synchronously as @gratux@lemmy.blahaj.zone recommended because in that case the data is only stored on one device and almost always accessed remotely. If the internet connection is gone, you’d no longer have access to the data and if the VPS dies, your data would be gone on all other machines too.
If you want to use Nextcloud anyways, that would be an option.
If all you want to do is have a shared synchronised state between multiple machines though, Syncthing would be a much lighter weight purpose-built alternative.
It’s really down to where you want the files to live. Sure synching would provide easy redundancy with a copy of the files on every machine, but that 20GB of documents or whatever would effectively become 100gb of files if it’s being synced to 5 different computers, eating up 20GB of space on every computer, meanwhile using a standard network share would give you a single centralized location with one copy of the data, then you just make backups according to whatever your backup scheme is.
It really depends on what it is you’re trying to share between machines.
I don’t use syncthing but something that fulfils a similar function (git-annex). My Documents repo is set up in such a way that all instances of the repo try to have a copy of everything because documents are very important data and don’t take much space. Other (larger) repos only try to have two or three independant copies; depending on how large and important their data is.
I think SFTP would work plenty. On linux you can use rclone to mount it, and Android has many file managers that support it (personal favorite is Total Commander with the SFTP plugin)
You could also certainly host a full Nextcloud instance, but it might be a bit overkill
