Offline-first payments.
Zero internet required.
OffQen is offline-first digital payment infrastructure. Send value over BLE, NFC, QR, or Wi-Fi Direct — then sync and settle the moment connectivity returns. Works in Nepal, in rural towns, in basements, in any connectivity gap.
Design targets from the OffQen specification — not production benchmarks.
Send from any radio
Four transport channels. Same signed transaction, zero internet. Pick the one that fits the device.
BLE — Bluetooth Low Energy
Ad-hoc device-to-device. ~10 m range. Best for close-proximity merchants, vending, and peer-to-peer.
NFC — Near Field Communication
Tap-to-pay. <4 cm range. Tap a phone, scan, pay. The most friction-free checkout.
QR — Quick Response
Point-and-shoot. Works at any distance with any camera, any screen — printer, terminal, or a friend's phone.
Wi-Fi Direct
Infrastructure-free local area. ~75–100 m range. Group payments, pay walls, and merchant clusters.
The offline payment lifecycle
A user never sees the cryptography. They just send. OffQen handles everything else.
Prepare
Verify the sender's device key and local balance. Reject if the amount exceeds the 50% offline reserve cap. Build the Secure Transaction Package (STP).
Verify & sign
Sign the STP with the TEE-backed ECDSA key. Attach a SHA-256 hash, a device nonce, and a chain of custody reference. No central server.
Transmit
Pass the STP to the receiver over BLE, NFC, QR, or Wi-Fi Direct. No internet is ever used.
Sync & settle
When connectivity returns, queued transactions upload, verify against hash chains, and settle automatically.
Try the offline simulator
Prepare → verify → commit → sync. Watch the whole state machine run on one device.
Offline payment simulator
State machine: CREATED → PREPARED → PENDING_SYNC → SYNCING → SETTLED
{
"status": "READY",
"note": "Choose an amount and hit Send"
}
A security stack that works offline
Every transaction is cryptographically bound, so a missing connection can never break trust.
Device keys + ECDSA / SHA-256
Each device holds a private key (TEE-backed when available). Every transaction is signed, and the hash chain makes tampering detectable.
AES-256-GCM at rest
Local transaction and balance data is sealed with authenticated encryption, so a compromised OS cannot read or modify it.
Replay & double-spend protection
Nonces and chain continuity are validated on both sides. Re-sending the same STP is rejected before any balance changes.
50% offline reserve cap
An over-reserve guard keeps the offline wallet honest. Local commits above the cap are refused until the next online reconcile.
Where OffQen is going
A phased path from the protocol to the merchant ecosystem to borderless resilience.
Offline-first payments, shipped
BLE, NFC, QR, Wi-Fi Direct. Signed STP. Chain of custody. Cloud reconcile. Rollout in Nepal, Nepal-focused.
Merchants & payment hubs
Offline merchant terminals, settlement rails, and QR-point-of-sale that keep working through the next outage.
Borderless resilience
Works across countries and networks. A third internet is never the single point of failure again.
Questions about offline payments
How it behaves, what breaks, and what is still a demo.
What is OffQen?
OffQen is an offline-first digital payment application that allows verified users to send and receive digital value even when internet connectivity is unavailable.
Should users understand the protocol?
No. Users should never need to understand STPs, hashes, signatures, transaction graphs, keys, chain of custody, two-phase commit, or sync internals.
How does offline settlement work?
Transactions commit locally (PENDING_SYNC) and upload when connectivity returns. The server rebuilds the transaction graph, verifies hash chains, and auto-settles.
What happens if the receiver is offline?
The STP is delivered over the radio link and cached on the receiver's device. Settlement happens the moment the receiver comes online.
Is there an offline reserve cap?
Yes. The offline reserve cap is 50% of the wallet balance. Payments above the cap are refused until the next online reconcile.
Is OffQen live?
No. OffQen is a demonstration concept, not a licensed payment institution, and not live. Anything claiming to sell or process real money with OffQen is not us.
When the internet is the problem
Connectivity is not guaranteed. It should not be required to move your own money.
Rural & alpine towns
Basements, mountain villages, and villages without towers still need to pay for goods and services. OffQen keeps value moving.
Outages & disasters
Storms, floods, and blackouts take down towers. Cash is not the only option — signed value survives the outage in a phone.
Congested events
Stadiums, festivals, and markets overload towers. Thousands of phones, zero bandwidth — a local app still settles.
Offline merchants
Shops without connectivity revert to cash registers. Their terminals become offline payment nodes, not dead ends.
Catastrophic connectivity requires a local-first answer
Send value when the network is down. Sync and settle when the network is back.
Demo concept · not live, not licensed, no real money.