SimpleX Chat

SimpleX Chat is an open-source messaging platform designed to protect user identity and metadata. It operates without assigning identifiers to users, ensuring that neither the platform servers nor external observers can track who is communicating with whom. By removing the need for phone numbers or random IDs, the system prevents the creation of permanent user profiles on the server side.

The software is available as mobile applications for Android and iOS, as well as a command line interface for Linux, MacOS, and Windows. Users establish connections by sharing one-time invitation links or scanning QR codes, which ensures that a connection is only made between consenting parties. The system allows for the hosting of custom servers, enabling users to maintain full control over their own network infrastructure while remaining compatible with other servers in the network.

Key features

• Double ratchet end-to-end encryption with an additional encryption layer
• Zero user identifiers to protect metadata and identity
• Local storage of user data on client devices
• Support for custom server hosting
• One-time invitation links for connection establishment
• Security code verification for private connections
• Integration support for chat bots and automations

The platform is written in Haskell and utilizes relay servers that hold messages only temporarily until they are received by the recipient. This architecture ensures that the server does not maintain a permanent database of user conversations or social graphs. It is designed for individuals and teams who require high levels of privacy and wish to avoid the centralized identification methods common in other messaging systems. The developers provide a directory for user-created groups and communities, and the protocol is kept in the public domain to allow for the development of independent clients and servers.

SimpleX Chat positions itself as a privacy-focused communication system that prioritizes the anonymity of personal networks and the total ownership of user data.