Set up an offline signer

Make a wallet on your offline device, let your everyday device watch it with one QR code, and keep the offline device offline for good.

An offline signer setup is two devices and one QR code between them. The offline device holds the keys; your everyday device watches the same wallet, so it can show balances and prepare payments, but it can't spend on its own.

#Before you start

• The offline device: a spare phone or laptop with AirWallet in Offline signer mode, or with AirWallet Offline. See Install for which to choose and how to get it there without the internet.
• The everyday device: AirWallet as an Everyday wallet, the AirWallet Chrome extension, or airwallet.tech/online.

Take the offline device offline before you go on: airplane mode on, Wi-Fi and Bluetooth off.

#1. Make the wallet on the offline device

On the offline device, tap Create a wallet (or + → Create a wallet) and write down the recovery phrase. If you already have a phrase, use Import instead. See Create or import a wallet.

#2. Show it to your everyday device

1. On the offline device, open the wallet and tap Receive.
2. Tap Show to my online wallet…

A QR code appears. If it's an animated one, it loops through its frames: leave it on screen until the other device has read it.

The code holds the wallet's addresses on each chain and other public information, never a key that can spend. For Monero and Zcash it also holds a view key (see below).

Until the offline device has seen any balances, its wallet screen shows No balances yet, with a Show to my online wallet button that does the same.

#3. Scan it on the everyday device

1. On the everyday device, tap Watch my offline wallet on the first screen, or + → Watch an address. (The Offline screen also has Watch an offline wallet.)
2. Tap Scan (in some layouts, Scan the code on the offline device) and hold the camera up to the offline device's code.
3. Optionally give the wallet a name, then tap Add.

The wallet now appears on your everyday device as a watched wallet. It shows balances and history, and Send on it prepares a payment for the offline device to sign. It can't spend on its own: the keys aren't there.

Receiving needs no signature, so you can get paid while the offline device stays in a drawer: your everyday device's Receive shows the wallet's addresses too.

#Monero and Zcash: the view key

Monero and Zcash payments are private: an address alone doesn't show what arrived. So for a recovery-phrase wallet, the code from Show to my online wallet also carries:

• Monero's private view key. With it, the everyday device sees what arrives and the amounts, but it can't spend. It also can't tell which coins are spent until your first send (see Your first offline payment). The Monero node never gets the view key: your everyday device downloads blocks and scans them itself.
• Zcash's viewing key (uview1…). With it, the everyday device sees everything the wallet receives and sends, with amounts and memos, and can make the proofs for a send. It can't spend: that needs the spending key, which never leaves the offline device.

If a view key leaks, you lose privacy (anyone with it can see those payments), never coins.

airwallet.tech/online says so before it keeps a code with a view key, and lets you watch without it (then it shows Bitcoin, Ethereum and Solana only).

A Zcash viewing key pasted on its own (exported from another wallet) is watched only: you can't send from it here.

#Try the loop once

Before you move much money, send a small amount to the new wallet and then spend it, signing on the offline device. That shows you the whole loop working, end to end. See Your first offline payment.

#Keep the offline device offline

The protection lasts exactly as long as the device stays offline. (Platform by platform: Keeping the offline device offline.)

• Keep it in airplane mode, with Wi-Fi and Bluetooth off, for good. Don't join a Wi-Fi network "just once".
• Use it only for AirWallet. No other apps on it.
• On Android, prefer AirWallet Offline. It has no internet permission, so Android itself blocks it. AirWallet in Offline signer mode blocks itself.
• Check it yourself. Settings → This phone: offline signer… explains why the device can't connect, and Try to connect shows the attempt being refused.
• Lock it. Turn on the app lock (Settings → App lock: off…). The air gap does nothing against someone who picks up the device and opens the app.
• Update without going online. Bring the new version over by USB cable or SD card; airplane mode can stay on. Update both devices to the same version: an older copy refuses codes from a newer one rather than misread them.
• Old Android phones: a factory reset puts the phone's old web engine back, and updating it again needs the internet. Avoid resetting the offline phone.

#Other apps

The offline device can also act as a QR signer for some other wallet apps (on the offline device: Receive → Use with another app), such as Sparrow and BlueWallet for Bitcoin, MetaMask and Rabby for Ethereum, Solflare and Backpack for Solana, Feather and Cake Wallet for Monero, and Zodl for Zcash. It works with the QR codes these apps use; support for several of them is new and hasn't been tried with every app yet. Some of these pairings are new: see Other wallets and hardware for which have been tried.