Allnet-xchat is a peer-to-peer (P2P) chat app. There is no centralized server and no single ID for any user. Instead, you name your contacts using the name or nickname you normally use to refer to them, then exchange keys -- one of the persons must enter a secret string from the other's screen. Messages are then exchanged confidentially.
Redesigned user interface.
With Family Sharing set up, up to six family members can use this app.