Signal's encryption protocol is open source, meaning anyone that it's freely available for anyone to inspect, use or modify. The encryption protocol is also used by another popular chat service ...

An image of the Signal app is shown on a mobile phone in San Francisco, March 18. LONDON — A magazine journalist's account of being added to a group chat of U.S. national security officials ...

Allies of the United States see the group chat between top U.S. officials about ... of one European diplomat about the discussion on the Signal messaging app about strikes on Houthi rebels.