Instead of Resilio Sync, I would suggest that people take a look at Syncthing. They have similar features but Syncthing is open source.
Syncthing is simply not designed for the mainstream. Resilio is. If Syncthing devs can fix that, I'll gladly start using it over Resilio with my non-technical friends.
(There's also a closed-source iOS app called fsync(), but I found it too slow/unstable to use.)