Signal is a free and open-source instant messaging and voice over IP application that uses end-to-end encryption to secure all communications to other Signal users. The app is available for iOS and Android, as well as for desktop. Signal is considered to be one of the most secure instant messaging apps available, and is recommended by privacy advocates, security experts, and even government officials. Signal uses the Signal Protocol, which is widely considered to be one of the most secure encryption protocols currently in use.
In addition to its end-to-end encryption, Signal also offers other features such as self-destructing messages, and the ability to verify the identity of contacts. Signal is also known for its commitment to user privacy, and is a non-profit organization that is financially supported by grants and donations.
How secure is Signal?
It is alleged that Signal app was among the tools used by the CIA as part of its hacking operations[Archive]. According to the leaked documents, the CIA had developed a tool called “Weeping Angel” which could be used to turn Samsung smart TVs into covert microphones, and it is reported that the agency had plans to develop similar capabilities for other internet-connected devices, including smartphones. However, it is important to note that these documents have not been independently verified, and the CIA has not confirmed the authenticity of the leaked documents.
Signal’s developers have not commented on the specific claims made in the Vault 7 leaks, but have emphasized that Signal app uses end-to-end encryption, and that the company does not have the ability to access user’s content or metadata.