Signal
Encrypted messages and calls. The app recommended by Snowden and virtually every security expert.
Description
Signal is the global reference for encrypted messaging. Developed by a nonprofit foundation, it encrypts messages, voice calls and video end-to-end. No data is collected, no ads are shown. The Signal protocol is used by WhatsApp itself for encryption. The app is free and open source.
Strengths
- Gold standard for encrypted messaging
- Nonprofit foundation, no ads, no data collection
- Protocol used by WhatsApp for its own encryption
- Free and open source
Limitations
- Requires a phone number to register
- Smaller user base than WhatsApp or Telegram
Recommended for
- Replacing WhatsApp or Telegram with a truly private messenger
- Group chats, voice and video calls with encryption
Compared to alternatives
Signal is the reference for encryption, recommended by the security community. Threema doesn't require a phone number. Element/Matrix is decentralized and self-hostable.