Signal — The Gold Standard for E2EE
Non-profit Signal Foundation. The Signal Protocol powers WhatsApp, Google RCS, and Messenger secret chats.
Pros
- Simplest UX — works like a normal messaging app
- Audited, battle-tested cryptography; no ads, no tracking
Cons
- Phone number required — links identity to account
- Centralized — Signal's servers, Signal's rules
Best for: journalists, activists, everyday secure messaging