Tox is a secure chat application with end to end encryption that allows for text, voice, and video chat.
You can use a number of Tox clients, each with different pros and cons. I highly recommend qTox though.
My ID: B540063A92D12D13788EBBD72F5574422F311FBCC7112B74154491762C000354C8BF60024BC5
Does Tox keep chat history?
Locally on your machine, yes.
Tox doesn't have their own servers to keep anything on. It works similar to torrents, or "peer 2 peer"... The only person you're connecting to is the other person using tox.