It's entirely P2P, so no 3rd party hosting of your files, no trusting someone's crypto/update schemes, or having to set up your own servers (although you still can easily add it to a VPS if you want offsite). There's also a nice mobile app:
You can also securely share directories with another person who uses Syncthing, I've found autosync directories are easier than using something like Airdrop for sharing photos with family.
I'm using them for years as a form of backup. Very reasonable priced, works flawlessly for me though I mainly use as a form of backup for a synced folder. GDPR compliant.
I've seen a HN poster promote filestash.app which looks like it's either self-host or hosted. I guess you might have to add in something like Spideroak, Backblaze, or tarsnap if you want to self host + backup.
Or Syncthing as others have pointed out.
I'm still thinking which is best. They're slightly different use cases. But generally, I'd only really trust it if there's open source, otherwise there's lock-in.
