Signal is one of the most trusted open-source communication apps on the market today. Formerly known as TextSecure, Signal uses the Signal protocol to provide its strong privacy features (hence the name).
Signal also uses end-to-end encryption to secure messages by default, making it nigh-impossible for any third party to intercept or monitor them. It's widely favored by individuals who prioritize confidentiality, from journalists and activists to those who value secure communications.
