Communicate Without Internet.
OffMesh turns your smartphone into an autonomous, delay-tolerant mesh node. Exchange end-to-end encrypted messages across Bluetooth Low Energy and Wi-Fi Direct without cell towers, centralized servers, or cellular data plans.
Built for Resilience When Infrastructure Fails
Engineered strictly under the Monochrome Minimal design specification and decentralized cryptographic principles.
Zero Infrastructure Required
Physical radios form an ad-hoc local mesh. Phones automatically discover nearby peers over BLE and Wi-Fi Direct with zero internet, zero SIM card, and zero cloud reliance.
End-to-End Cryptography
Double Ratchet protocol combining X25519 key agreements and ChaCha20-Poly1305 authenticated payload encryption. Intermediate relay peers cannot read or inspect plaintext.
Store & Forward Relaying
Delay-Tolerant Networking (DTN) enables packets to hop from device to device. A message travels through moving participants until encountering the recipient.
Honest Delivery Feedback
No false "sent" checkmarks. OffMesh transparently displays Queued, Forwarded, Gateway Uploaded, and cryptographically verified Delivered states.
How OffMesh Packets Hop Off-Grid
Experience delay-tolerant store-and-forward peer relaying in real-time. Click to send an encrypted packet between offline devices.
Opportunistic Store & Forward Simulator
Honest Delivery Feedback
Unlike traditional apps that flash fake "Sent" ticks when you are offline, OffMesh provides cryptographically authenticated, transparent delivery states so you always know where your message is.
Queued Locally
Stored in local encrypted database. Awaiting route or peer contact via BLE/Wi-Fi Direct.
Relayed / Forwarding
Encrypted blob accepted by intermediate peer. Peer cannot inspect plaintext payload.
Uploaded to Sync Gateway
Encrypted blob stored on server cache for 7 days TTL. Transparently disclosed that recipient has not yet fetched it.
Delivered & Verified
Recipient's device decrypted packet and returned signed Ed25519 delivery receipt acknowledgment.
Why OffMesh Outperforms Conventional Messengers
Comparing operational capability during grid failures, natural disasters, and off-grid travel.
| Feature Capability | OffMesh | Traditional SMS | Internet Messengers (Signal/WhatsApp) | Proprietary LoRa Radios |
|---|---|---|---|---|
| Works with Zero Internet | ✓ Yes (BLE & Wi-Fi Direct) | ✗ Requires Cell Towers | ✗ Requires Internet | ✓ Yes |
| Standard Hardware (No Dongles) | ✓ Standard Smartphone | ✓ Standard Phone | ✓ Standard Smartphone | ✗ Requires $100+ Hardware |
| Zero-Knowledge End-to-End Encryption | ✓ Yes (Double Ratchet) | ✗ Unencrypted Plaintext | ✓ Yes | Partial / Static Key |
| No Phone Number Required | ✓ Cryptographic Keys Only | ✗ Requires Telco SIM | ✗ Requires Phone Number | ✓ Yes |
| Multi-Hop Store & Forward | ✓ Automatic Peer Hops | ✗ Central Gateway Only | ✗ Central Server Only | Limited Packet Size |
Download OffMesh Today
Available now as a signed Android App Bundle (.aab) for Google Play Store deployment and direct APK release packages.
Everything You Need to Know
Have questions about offline radios, cryptography, or compliance? Here are direct technical answers.
How does OffMesh send messages without internet or cellular connectivity?
OffMesh uses the physical Bluetooth Low Energy (BLE) and Wi-Fi Direct radios already inside your smartphone to form an ad-hoc, decentralized mesh network. Devices within radio proximity (typically 30 to 100 meters) discover each other and exchange encrypted message packets directly. Using delay-tolerant store-and-forward routing, messages hop across intermediate peer phones until they reach the recipient, without ever touching a cellular tower or internet router.
Can intermediate relay peers read or tamper with my private messages?
No. OffMesh uses zero-knowledge end-to-end encryption combining the X25519 Double Ratchet protocol with ChaCha20-Poly1305 authenticated encryption. Intermediate relays only carry opaque cryptographic envelopes with blinded hop routing headers. Neither intermediate peers nor the OffMesh project can decrypt or alter your messages without being cryptographically rejected.
Does OffMesh require or track my GPS location, phone number, or identity?
OffMesh collects zero personal data, zero phone numbers, and zero email addresses. Your identity is an Ed25519 cryptographic keypair generated locally in your phone's hardware Keystore. On Android, Bluetooth discovery is registered with the neverForLocation flag, ensuring that location tracking is never performed or accessible.
What happens if someone has internet access while others are offline?
OffMesh supports opportunistic sync gateways. If any device in the mesh encounters an active internet connection, it can optionally upload encrypted ciphertext blobs to an ephemeral gateway cache (7-day TTL). When the recipient reconnects, their device retrieves and decrypts the message. If no internet is ever found, the mesh continues operating purely peer-to-peer.
Where can I download OffMesh for Android and iOS?
OffMesh is available as a signed Google Play Store App Bundle (.aab) and direct release APK downloads via GitHub Releases. Every release is built automatically and cryptographically signed through our reproducible CI/CD pipeline.