Quick update for Syncthing users: an official Syncthing Ubuntu / Debian repository was released recently and it provides builds for amd64, i386 and arm.
Syncthing is a cross-platform peer-to-peer file synchronization client/server application written in Go. The tool is similar to BitTorrent Sync (but it's open source as opposed to BT Sync), and it's used to synchronize files between computers.
The app comes with an option to update the binary to the latest version however, there are new Syncthing releases every few days so using a repository to automatically update the app is a must if you're a regular Syncthing user (there's also an alternative: Syncthing GTK, which automatically updates the Syncthing binary).
The packages from the new official Syncthing Ubuntu / Debian repository are slightly experimental for now, as this repo was just released, but they should work on any recent Ubuntu and Debian version. Right now, the packages only provide the main binary and some README files, without any startup scripts, etc. but this may change.
In the future, this repository might also be used to host various third-party Syncthing packages, such as Syncthing GTK (right now, this can be installed from the min WebUpd8 PPA).
Install Syncthing in Ubuntu / Linux Mint / Debian using its official repository
To add the official Syncthing (release) repository in Ubuntu, Linux Mint or Debian (and derivatives), use the following commands:
sudo apt-get install curl curl -s https://syncthing.net/release-key.txt | sudo apt-key add - echo "deb http://apt.syncthing.net/ syncthing release" | sudo tee /etc/apt/sources.list.d/syncthing-release.list sudo apt-get update sudo apt-get install syncthing