Twitter co-founder launches beta version of decentralized messaging app Bitchat

Twitter co-founder Jack Dorsey has launched the beta version of BitChat, a decentralized peer-to-peer messaging app that works without internet access.

Announced on July 7 via a post on X, BitChat operates over Bluetooth Low Energy mesh networks, meaning it allows nearby devices to form a self-organizing network without relying on servers or cell towers. Short-range Bluetooth allows messages to move between devices, with each device serving as a sender and a relay.

This enables communication even in the absence of an internet connection, which is helpful in censorship-heavy environments, protests, and natural disasters. According to Dorsey, BitChat began as a weekend experiment to explore protocols like message relays, encryption models, and store-and-forward mechanisms. 

BitChat messages are meant to be transient, which means they aren’t kept on file forever. Messages are stored in the device’s memory by default, and they vanish after delivery or a predetermined amount of time. This reduces data exposure and is consistent with BitChat’s privacy-first philosophy.

The platformm employs modern encryption standards for security. A cryptographic technique called X25519 is used in private messages to safely transfer keys between devices, ensuring that only the intended recipients can read the messages.

AES-256-GCM, a widely respected encryption algorithm renowned for its speed and security, is used to encrypt messages after the key has been exchanged. Group chats (or “rooms”) can also be password-protected, with keys generated using Argon2id, a memory-hard algorithm that prevents brute-force attacks.

In order to provide dependable delivery even in interrupted environments, BitChat also features a “store and forward” system that temporarily stores messages for offline users and delivers them once they reconnect. 

BitChat is open-source on GitHub and accessible in beta via Apple TestFlight. It is still experimental, Dorsey stressed. Its objective is to establish a decentralized, safe messaging system that is immune to censorship, surveillance, and reliance on tech giants.

The announcement builds on Dorsey’s longstanding support for decentralized platforms like Nostr and comes after he left Bluesky’s board in 2024. With BitChat, Dorsey appears to be doubling down on the cypherpunk vision of peer-to-peer communication which is private, resilient, and independent from centralized control.