Threema is a Swiss end-to-end encrypted messenger that lets you register anonymously without a phone number. The app is a one-time purchase of about CHF 3.99, has an open source client audited by ETH Zurich, and is the secure messaging choice for privacy-focused users and enterprises.
Wire is an end-to-end encrypted communication platform founded in Zurich, Switzerland in 2014, offering encrypted messaging, voice and video, with open-source core code and self-hosting support, adopted by German federal agencies.
Teamwire is an enterprise secure messaging platform founded in 2015 in Munich, Germany, using AES-256 end-to-end encryption with EU-hosted data, GDPR and ISO 27001 compliance and private deployment support.
Symphony is a secure communication platform for the financial industry founded in 2014 in New York, United States, offering end-to-end encrypted messaging, compliance archiving, and trading workflow integration to hundreds of thousands of financial professionals.
Session is a decentralized end-to-end encrypted messaging app that lets you register anonymously with a 66-character Session ID and routes messages through 1000+ service nodes, a leading tool for privacy and anonymous communication.
Element is an end-to-end encrypted messaging client built on the open Matrix protocol, headquartered in London, United Kingdom, with E2EE by default, decentralized federation, open source, and ISO/IEC 27001:2022 certification.
Signal is operated by the non-profit Signal Foundation using Signal Protocol end-to-end encryption, backed by $50 million in funding, free forever with no ads, and is the security benchmark recommended by privacy experts worldwide.