Bitchat: Jack Dorsey’s Bluetooth Chat App That Works Without the Internet

Bitchat: Jack Dorsey’s Bluetooth Chat App That Works Without the Internet

Built by the co-founder of Twitter and Block, Inc., Bitchat creates a mesh network from smartphones — and requires no servers, accounts, or cell service to send a message.

In the summer of 2025, Jack Dorsey announced something that surprised even longtime followers of his work: a Bluetooth-based chat application that requires no internet connection, no phone number, and no account to use. He called it Bitchat.

The description in the GitHub repository is just four words: “bluetooth mesh chat, IRC vibes.” That minimalism turned out to be fitting for a project that, in Dorsey’s telling, is less about market competition and more about a different philosophy of communication.

How It Works

Bitchat operates on Bluetooth Low Energy (BLE), the same radio technology that connects wireless earbuds and fitness trackers. When two phones running Bitchat come within Bluetooth range, they connect directly — no router, no carrier, no cloud.

The application forms a mesh network: each device acts as both a recipient and a relay, forwarding messages onward. A message can travel up to seven hops through intermediate devices, extending practical range well beyond what a single Bluetooth link could cover.

When internet access is available, Bitchat can also route messages through Nostr, a decentralised protocol with a global relay network. This allows location-based channels via geohash coordinates — effectively letting users join a chat room tied to a city block, a neighbourhood, or an entire region.

The app switches between these two layers automatically. Bluetooth is always preferred; Nostr serves as a fallback. If neither is reachable, messages queue locally until connectivity returns.

“A decentralised mesh network where devices communicate directly — no internet required, no servers, no phone numbers.”

Encryption and Privacy

For encryption, Bitchat uses the Noise Protocol Framework — the same foundational system underlying Signal’s encrypted calls. It provides end-to-end encryption, forward secrecy (meaning past messages stay protected even if a key is later compromised), and authenticated private messaging.

Privacy is also built into the identity model. Users are assigned a randomly generated nickname on first launch. There is no mandatory registration and no persistent identifier stored on a central server. The app also features an Emergency Wipe: three taps on the logo immediately erase all local data, with no confirmation prompt.

IRC Vibes — and Some Caution

Dorsey has said openly that the app takes inspiration from IRC, the bare-bones chat protocol that was central to open-source communities throughout the 1990s and 2000s. Classic IRC commands like /msg and /who are supported.

Early reception was enthusiastic, but not without friction. Shortly after the app entered beta on Apple’s TestFlight platform — quickly filling its 10,000-user limit — a security researcher reported a vulnerability that could allow one user to impersonate another. Dorsey acknowledged the issue and added a note to the repository stating that the project is a work-in-progress, had not yet undergone an external security review, and might not yet fully meet its stated security goals.

Availability and Limitations

The iOS app is available on the App Store. An Android version, maintained by the community under the permissionlesstech GitHub organisation, is available as an APK download and has received regular updates — including background persistence for mesh support and built-in Tor integration for enhanced privacy when online.

Practical limitations remain. Bluetooth mesh range is constrained by physics: under ideal conditions, multi-hop coverage spans tens to perhaps a few hundred metres, depending on how many devices are present and willing to relay. In sparse environments with few users nearby, the mesh has little to relay through.

For large, dense gatherings — music festivals, protests, conference halls, disaster-response zones — those constraints matter far less. This is precisely the use case Dorsey designed for: resilient communication when traditional networks are unavailable, overwhelmed, or deliberately shut down.

“If every conventional communication method fails, there is still one more option.”

Why It Matters

Bitchat is not a replacement for WhatsApp or iMessage. It does not aspire to be. What it demonstrates is that the hardware already in most people’s pockets — a Bluetooth radio, a capable processor, modern cryptography — is sufficient to build a functioning communication network from scratch, with no intermediary required.

That proposition has attracted serious attention. Events like Cuba’s 2024 nationwide blackout and the 2023 earthquake in Turkey — where cellular infrastructure was disrupted for days — have shown the real-world cost of over-reliance on centralised networks. Tools like Bitchat are a reminder that other architectures are possible.

Dorsey released the iOS code under the Unlicense, placing it effectively in the public domain. The project can be used, copied, modified, or built upon by anyone, for any purpose, with no restrictions. In a technology landscape where open-source projects often come with aggressive marketing, that restraint is itself a statement.