Signal, a secure messaging app, gained attention when top White House defense and national security leaders were found using it for discussions about plans for an attack on targets in Yemen.
Signal's popularity among government officials, activists, and journalists is due to its end-to-end encryption, which ensures that no one, including Signal itself, can read intercepted messages.
However, end-to-end encryption is not the only consideration when choosing a secure messaging app, and there is no such thing as perfect security.
Factors to consider when selecting a secure messaging app include encryption, metadata privacy, available features, open-source code, decentralized server network, and the company's data collection practices.