♦ The Signal is a cross-platform centralized encrypted messaging services. It is developed by the Signal Technology Foundation and Signal Messenger LLC.
♦ The non-profit Signal Foundation was established in 2018 with an initial investment of US$50 million by Brian Acton.
♦ It uses the Internet to send one-to-one messages and group messages, which can include files, voice notes, images and videos.
♦ It can also be used for one-to-one calls and grouped voice and video calls.
♦ Signal uses a standard cellular phone number as an identifier and protects all communications with other Signal users through end-to-end encryption.