I did the same. Plus also I'm using on my Android phone. Replaces Dropbox completely unless I want to share something with other people. But for that case I usually use Sharing feature from Synology NAS.
Oh I also have shared folders with other people. We used to use it for sharing audio files between podcast presenters, which worked well enough. I have half a dozen folders in my $HOME, shared with different groups of people.
I also have Syncthing installed on my home server which gets backed up. So I have a copy of all my files backed up there, in the event a laptop goes missing or dies.
The only use case I haven't yet covered is an off-site backup of my Syncthing folder, which would be sensible. I just don't know who I can trust with it.
A word of caution for anyone planning to use syncthing for backups.
Syncthing is designed as a sync solution but not explicitly for backups. You need some extra setup on top of the defaults for building a reliable backup solution.
If not setup correctly, any "mistakes" from one of the devices will automatically be synced to other devices and cannot be retrieved back.
In the case of a lost/stolen device, make sure you remove the device as soon as possible.
If not a bad actor now possessing the device can delete and sync that back to your "back-up" devices too.
You can try to use the untrusted device functionality, the data is encrypted on the sending device. Word of caution, it is still beta, an in my experience, it is kinda hit or miss, for some folders it worked beautifully, for another, it simply did not sync after the initial configuration.
You can install a cron job which compresses, encrypts and rsyncs/rclones your home backup weekly to somewhere. Or you can use BackInTime which can automatically encrypt and only backup changed files, again to a remote location.
