The latest version available is Atom 1.14, which has been recently released, bringing changes and new features.
The latest Atom versions are available via some third party PPA, so installing an up to date version of the text editor on Ubuntu 16.10 Yakkety Yak, Ubuntu 16.04 Xenial Xerus, Ubuntu 14.04 Trusty Tahr and derivative systems like Linux Mint 17.x, Linux Mint 18.x and Elementary OS 0.4 Loki and Elementary OS 0.3 Freya systems should not cause too many problems.
You need to add the PPA to your system, update the local repository index and install the atom package:
$ sudo add-apt-repository ppa:webupd8team/atom
$ sudo apt-get update
$ sudo apt-get install atom
If you are not happy with Atom and want to uninstall it, do:
$ sudo apt-get remove atom