How it works

Hopper builds a live encrypted mesh from the radio chips already inside your phone. Here’s how a message travels from you to anyone nearby.

No towers.Just physics.

Phone to phone · up to 1,024 peersEnd-to-end encrypted · 0 bytes stored

Five steps

From install to delivered. Exactly how the app does it.

Install

Download Hopper, pick a username and an avatar. That pair is all people nearby ever see — no phone number, no social account, nothing tied to your real name.

Identity keys generated on-device

Discover

Your phone advertises and scans at the same time over Bluetooth LE, Wi-Fi Direct on Android and Multipeer on iOS. Peers introduce themselves the moment they are in range.

BLE service 8E9A2B00 · iOS ↔ Android

Handshake

Each pair runs a Noise XX handshake then exchanges signing keys. Scan a peer’s QR to verify the key out of band.

Noise_XX_25519_AESGCM_SHA256

Relay

No direct link? The message is flooded through neighbours with a hop budget of 7 (16 in Large Venue Mode). Each node drops duplicates it has already seen and forwards the rest.

TTL 7 / 16 · 3-minute duplicate window

Deliver

Relays only ever carry ciphertext, and every broadcast is Ed25519-signed so no node can forge or tamper with it in flight.

Signed envelope · 24-hour freshness window

Sealed at the source

Every message is sealed inside a Noise session before it leaves your phone, so the peers relaying it only ever move ciphertext.

Nothing kept

A relay remembers only a message id, for three minutes, so it can drop duplicates. There is no server and no log.

No identity on the mesh

No phone number and no sign-up to message. Your X25519 and Ed25519 keys are generated on the device and stay in its secure storage. A paid plan takes your name and email for billing only — the mesh never sees them.

Ready to hop off the grid?