Open Whisper Systems' Signal is an open-source, end-to-end encrypted messaging client which can handle your regular SMS/MMS traffic, as well as (better) encrypted text communication between any number of Signal users, and encrypted voice calls. It not only encrypts content in transit, but stores it encrypted on your device as well. It has clients for iOS and Android. It also has a beta desktop app in the form of a Chrome app which can sync with your phone.

https://theintercept.com/2016/06/22/battle-of-the-secure-mes...