Signal 8.28.0

Signal: private messaging with strong encryption and minimal tracking

Signal is a cross-platform messaging app developed by a nonprofit foundation that emphasizes privacy, security, and a streamlined user experience. It uses the open-source Signal Protocol to deliver end-to-end encryption for one-to-one and group conversations, voice and video calls, attachments, and other message content, while deliberately limiting the metadata retained on its servers.

Security and privacy features

• End-to-end encryption for messages, voice and video calls, attachments, and group conversations, implemented via the open-source Signal Protocol.
• Minimal metadata collection: account information stored on servers is intentionally limited to reduce the surface for correlation or exposure.
• Registration lock and optional PIN to protect profile settings and prevent unauthorized re-registration of a phone number.
• Ephemeral options including configurable disappearing messages and view-once media for time-limited content.
• Platform-dependent options for preserving conversations when moving devices, including encrypted local backups and secure transfer mechanisms.
• Contact discovery designed to avoid uploading address books in the clear, using privacy-preserving techniques to match contacts without broadly exposing contact lists.

Calling, chat, and group capabilities

• Encrypted voice and video calls for individual and group conversations, using the devices data connection rather than SMS/MMS.
• Rich messaging features including text, voice notes, photos, videos, documents, GIFs, and location sharing, all covered by the same encryption protections.
• Group chats with member and admin controls, threaded replies, reactions, mentions, and invite links to facilitate coordination while maintaining privacy defaults.

Design, usability, and platform support

• Clean, minimal interface across mobile and desktop clients—Android, iOS, Windows, macOS, and Linux—with secure synchronization between linked devices.
• Lightweight behavior over cellular and Wi-Fi connections, relying on the devices internet link to send messages and place calls.
• Accessibility and customization options such as adjustable message font size, dark mode, and granular notification controls.
• Open-source codebase available for inspection and contribution, supporting transparency and third-party auditing.

Support, governance, and funding

• Operated by a nonprofit organization and funded through grants and donations rather than advertising or data monetization.
• Official help resources and documentation cover installation, privacy features, account management, and troubleshooting.
• Ongoing development with regular updates that address security and usability, informed by community and independent input.

Practical use cases

• Individuals seeking encrypted, advertising-free messaging and calling with minimal data collection.
• Professionals and others who require communication with reduced metadata exposure for sensitive discussions.
• General users who want a straightforward messaging app with cross-device support and privacy-focused defaults.