The Courier

Your Secure Air-Gap Interface

The Courier is now a standalone Progressive Web App (PWA) hosted at courier.safekeepbitcoin.com. It transmits text and files between your online computer or phone and SafeKeepVault using high-density QR codes — no cables, no USB swaps, no radio. All processing happens locally in your browser; no data is ever uploaded, transmitted, or stored on a server.

Because it is a PWA, you can install The Courier directly to your iOS or Android home screen for offline-ready, instant access — no app store required. On iOS, tap the Share button in Safari and choose Add to Home Screen. On Android, tap the browser menu and choose Install app. Once installed, it launches like a native app and works even without an internet connection.

• Transmit Mode — Encode any file or text string into a high-density QR code. Simply point your laptop or phone camera at your screen to reassemble the data on the other side.
• Receive Mode — Use your webcam to scan a QR code from the vault. This instantly brings your signed transactions or data back onto your online machine, ready to be sent to the network.
• PSBT files — For wallets that only work with files, such as Trezor Suite, The Courier carries the transaction both ways. Send the unsigned .psbt file to the vault’s Scan Unsigned PSBT; after signing, choose the File (Courier) export and receive the signed file here, ready for your wallet to open.
• Relay — A phone can pass a code along: receive a QR code, an animated QR (UR or BBQr, such as a PSBT from Sparrow) or a file, then tap Relay to play it straight back out to another camera, without saving or retyping anything.

Streamlined Vault Authentication

The Courier also serves a critical security function: generating the QR credential used to unlock your SafeKeepVault Encrypted Partition every time you boot.

The recommended workflow

1. Generate a High-Entropy Password — Use any password manager to create a long, fully random credential (e.g., 20+ characters). This remains your primary digital backup.
2. Generate the QR Credential — Paste the password into the Transmit tab using “Text / Password” mode. A static QR code is generated instantly and locally within your browser.
3. Save the QR on Your Phone — Save the QR image as a file on your phone, or as an attachment in your password manager, and open it whenever you unlock the vault. The QR opens nothing on its own: someone would also need your SafeKeepVault USB drive. Keep the password itself in your password manager, so losing the phone never locks you out (more on the unlock QR).
4. Instant Unlock — Upon every boot, display your phone to the SafeKeepVault camera. The system reads the QR and unlocks your vault instantly, eliminating the need for manual entry and allowing you to utilize unbreakable passwords without the inconvenience of typing.