Knit

An offline, serverless mesh messenger for Android — end-to-end encrypted, no internet, no accounts, no Google Play services.

Your phones talk directly to each other over Wi-Fi Aware and Bluetooth LE, and relay for one another hop by hop.

Knit needs no internet connection, no cell service, no accounts, and no servers. It forms an ad-hoc mesh directly over Wi-Fi Aware (NAN) and Bluetooth LE, running both radios at once. Send a message and it goes to every device in range; each of those re-transmits it onward, so messages leap-frog across phones with no infrastructure at all. Duplicates are discarded, hop-count and TTL bound the flood, and a store-and-forward layer carries what a single flood doesn't reach.

   ┌─────────┐   Wi-Fi Aware / BLE   ┌─────────┐   Wi-Fi Aware / BLE   ┌─────────┐
   │ Phone A │ ────────────────────► │ Phone B │ ────────────────────► │ Phone C │
   └─────────┘   send + relay        └─────────┘   relay (dedup)       └─────────┘
        │                                 │                                 │
   originates a           overhears & re-floods (jittered,          delivers — even though
   signed, encrypted      suppressed) — only carries ciphertext     A was never in its range
   frame once             it can't decrypt

• Two radios, no GMS. Wi-Fi Aware and Bluetooth LE run simultaneously behind one transport seam, with no Google Nearby dependency. A device with only one of the two still meshes over that one.
• End-to-end encrypted. Direct and group messages are sealed per-message (AES-256-GCM), wrapped to each recipient (HPKE/X25519), and signed (Ed25519), so relays only ever carry ciphertext. Identity keys are hardware-backed and verifiable in person by safety number or QR code.
• Store-and-forward. A message whose recipient isn't in range is held in encrypted custody and re-offered when a path to them appears, so phones that meet only briefly still backfill each other.
• Reproducible builds. F-Droid rebuilds each release from source and byte-compares it against the APK we publish before distributing it.

Android 10+ (API 29). Once installed, Knit can hand itself to a nearby phone over the mesh — no store and no network required.

Knit is free and open source, with no ads, no tracking, and no accounts.