Here you'll find links to all available versions of Swift.
Swift 4.0 (Current)
Swift 4.0 is the current release of Swift, it is available for download on Windows and Mac OS X (10.9+) as well as an AppImage for 64-bit Linux systems. The source code of Swift and Swiften is also available as a download along with the GPG signature.
To install and stay up to date with the latest releases on Ubuntu Linux and Debian, you can add the following APT lines (depending on your distribution) to the list of Software Sources in Synaptic Package Manager or /etc/apt/sources.list.
Ubuntu Xenial Xerus (16.04)
deb https://swift.im/packages/ubuntu/xenial release main
deb-src https://swift.im/packages/ubuntu/xenial release main
Ubuntu Artful Aardvark (17.10)
deb https://swift.im/packages/ubuntu/artful release main
deb-src https://swift.im/packages/ubuntu/artful release main
Debian 8 (jessie)
deb https://swift.im/packages/debian/jessie release main
deb-src https://swift.im/packages/debian/jessie release main
Debian 9 (stretch)
deb https://swift.im/packages/debian/stretch release main
deb-src https://swift.im/packages/debian/stretch release main
Note that these packages require that you install our key in the package manager list of trusted sources.
The main changes since 3.0 are outlined in the 4.0 Changelog.