Note: With the release of Lync Server 2013 in October 2012, a new collaboration feature "Persistent Group Chat" which allows multi-party chat with preservation of content between chat sessions was introduced. However, only the native Windows OS client and no other platform supports this feature at this time. The main new features of this version are the addition of real-time multi-client collaborative software capabilities, (which allow teams of people to see and simultaneously work on the same documents and communications session). Lync and Skype for Business implement these features as follows: