Signal

Languages: English (Various other languages are also accessible on Signal)

Signal is a messaging app with features like one-to-one messages, groups, stickers, photos, file transfers, voice calls, and even video calls anywhere in the world without SMS or MMS fees. Signal messages and calls are always end-to-end encrypted and engineered to keep your communication safe. The app also include mechanisms by which users can independently verify the identity of their contacts and the integrity of the data channel.