Syncthing

Syncthing is a peer-to-peerfile synchronization utility, designed to sync files between devices on a local network or between remote devices over the Internet. It runs on Windows, macOS, Linux, Android, iOS, *BSD and illumos. The software is free and open source, and its version 1.0 was released in 2019 after 5 years in beta.

The Syncthing server runs in the background as a daemon and provides a graphical user interface to the user for configuring the shared folders and devices. The interface is accessed in a web browser using the localhost address http://127.0.0.1:8384. Data security and safety are built into its design with all Syncthing data transfers encrypted using TLS.