That's it Tails Project just released the first release candidate of live OS Tails 2.6 RC1, a live operating system which runs on every computer and leaves no traces either on the machine or on the internet.
This particular functional Tails was used by former NSA employee Edward Snowden to remain hidden on the internet.
The new version incorporates some important news characteristics and changes, among which we can mention the upgrade to the latest Tor 0.2.8.6 , icedove improvements (1:45.2.0-1~deb8u1+tails1) an email and news suite.
The new version also contains many other small but useful improvements, such as firewall and kernel hardening, and support for languages other than English. You can see the changelog of the new version from here.
Download the new operating system