Official Syncany APT Repository

1. Add the Syncany Public Key

$ sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys A3002F0613D342687D70AEEE3F6B7F13651D12BD

2. Add APT Repository

For releases:
$ sudo sh -c "echo deb http://get.syncany.org/apt/release/ release main > /etc/apt/sources.list.d/syncany.list"

For snapshots (daily, or more often; things might break):
$ sudo sh -c "echo deb http://get.syncany.org/apt/snapshot/ snapshot main > /etc/apt/sources.list.d/syncany.list"

3. Install Syncany

$ sudo apt-get update
$ sudo apt-get install syncany
$ sudo apt-get install syncany-plugin-gui
$ sudo apt-get install syncany-plugin-ftp
$ sudo apt-get install syncany-plugin-webdav
$ ...