AirWallet Online

airwallet.tech/online is the watch-only web version of AirWallet's everyday side: watch your offline wallet, prepare payments as QR codes and send what your offline phone signed, with nothing to install.

#The everyday half of AirWallet, in a browser tab

Here's the part that still surprises me: open airwallet.tech/online on any computer, hold your offline phone's code up to the webcam, and a moment later a plain web page is showing that wallet's balances, Monero and Zcash included, worked out by scanning the blockchain right there in the tab. Nothing to install, no account, and no key ever arrives. The page talks only to each chain's public servers; airwallet.tech gets nothing from it.

So you can do the whole loop on a computer or phone where you'd rather not install an app. The page prepares a payment as a QR code, your offline phone checks it and signs, and then you scan the phone's answer back and send it. That's the same loop the AirWallet app runs, and it uses the same code underneath.

#What it does, and what it never does

AirWallet Online does what the everyday wallet does for a watched wallet:

• Shows balances and transaction history for the wallets you watch.
• Prepares payments as QR codes for your offline phone to check and sign.
• Scans the signed answer, checks it with the network, and sends it.
• Shows a balances code your offline phone can scan, so the phone can show balances too.
• Gives you receive addresses and their QR codes.

It never does these things:

• It never holds a private key, a recovery phrase or a backup. It can't sign anything. Your offline phone does all the signing.
• It never sends anything to airwallet.tech. It talks straight to the public servers for each chain (listed under "Who the page talks to" below).

#Watch your offline wallet

1. On your offline phone, open the wallet, then go to Receive → Show to my online wallet.
2. On airwallet.tech/online, select Watch my offline wallet. (After you've added your first wallet, use the + button.)
3. Select Scan with the camera and hold the phone's code up to it. You can also copy the code as text on the phone and paste it into Or paste it.
4. Give the wallet a name if you want one, then select Watch.

The code from your offline phone holds that wallet's addresses and no keys. Any plain Bitcoin, Ethereum or Solana address works too.

To stop watching a wallet, open its ⋯ menu and select Stop watching it. That only forgets the wallet on this page. The wallet and its coins stay on your offline phone, and you can watch it again any time.

#Monero and Zcash: the view key

You can't see a Monero or Zcash balance from an address alone, because those coins are private. To show them, the page needs the wallet's view key (Monero) or viewing key (Zcash). A code from your offline phone includes these for a recovery-phrase wallet.

Before the page keeps a code like this, it warns you with the message "This code has a view key". With the key, the page can see every payment the wallet receives and sends: amounts, times and the whole history. It can never spend.

You can choose:

• Watch with them: the page shows Monero and Zcash too.
• Watch without Monero or Zcash: the page drops those keys and watches the other coins only.

The keys stay in this browser only. On a shared computer, set a password first (see "Settings" below) so that what's kept here is sealed.

How the page finds Monero and Zcash balances:

• Monero goes through Cake Wallet's public node. It's the one public Monero node that answers web pages.
• Zcash goes through zec.rocks.
• These servers only see which blocks the page fetches. The page does the scanning with your view keys itself.
• The first look takes a while, because the page downloads and scans blocks. The line under the coin shows how far it has got.
• For a watched Monero wallet, the page counts what arrived. What the wallet has spent shows only after its first payment from this page.

#Send a payment

1. Open the wallet and select Send.
2. Choose the Asset, fill in To and Amount. You can scan an address or a payment link with the scan button next to To, or use Max. For Bitcoin, also choose the Speed: Fast, Normal or Slow.
3. Select Make the code. The page shows the payment as a QR code ("Scan it on your offline phone"), with what it pays and the fee.
4. On your offline phone, select Scan, check what the phone shows, then sign.
5. Back on the page, select Scan signed code → and hold the phone's signed code up to the camera. If you can't use the camera, paste the text instead, then select Check.
6. Check the Confirm screen, then select Send. The page then tells you how the payment is doing, up to "In a block. Done."

Some things to know:

• A long code is shown as an animated code. Hold it in front of the phone's camera until the phone has read it. Tap a code to make it bigger.
• A Solana code renews itself every 15 seconds, because it includes Solana's recent blockhash.
• Copy as text copies the code if you want to move it some other way.
• The first Monero payment from a watched wallet takes one extra round trip: the offline phone first tells the page which coins are spent. After that, each payment takes one round.

You can also get to this through the Offline button in the dock. It offers Scan a signed payment, New payment and Balances for the offline phone.

#Show balances on your offline phone

Your offline phone never connects, so it only knows balances when you show it this code.

1. Select Offline, then Balances for the offline phone. (Or open a wallet's ⋯ menu and select Show balances to the offline phone.)
2. On the offline phone, select Scan and hold it up to the code.

The phone then shows those balances as of now. Every payment code you make also carries the latest balances.

#Receive

Select Receive and choose the coin's tab. For a recovery-phrase wallet's Bitcoin, the page gives you a fresh address each time ("Address #N"). New address moves on to the next one. All of them belong to the same wallet.

#Settings

Select the gear button to open Settings.

#Use your own Solana server

Solana's free public servers don't answer web pages when it comes to token lists and activity. So on this page you see SOL itself, but not your Solana tokens or history, until you add a server of your own.

1. Get a Solana server address (an RPC URL) from Helius (it has a free plan), Alchemy or QuickNode.
2. Paste it into Solana server and select Save.

The page can only connect to those three providers, because of its security policy. The address is kept only in this browser.

#Set a password

1. In Settings, under Password, select Set a password.
2. Type a password of at least 8 characters, twice.
3. Choose Lock by itself after: Never, 5 minutes, 15 minutes or An hour.
4. Select Set the password.

What the page keeps here (addresses, names, balances and any view keys) is then sealed with your password, using Argon2id. Lock now locks the page straight away, and Turn off removes the password.

If you forget the password, select Forgot it? on the lock screen. The password can't be recovered, so you type ERASE, the page erases its copy, and you watch your wallets again from the offline phone. Your coins aren't touched.

#Install it as an app

You can install AirWallet Online like an app. Once it's installed, it opens without a connection too, and shows the last balances it saw.

On an iPhone:

1. Open airwallet.tech/online in Safari.
2. Tap the Share button, then Add to Home Screen.

On an iPhone, the installed app keeps its own wallets, separate from Safari's. Add your wallets again in the app.

On Android or a computer, in Chrome or Edge:

1. Open airwallet.tech/online.
2. Open the browser menu and select Install app. On Android it may say Add to Home screen.

If your browser offers it, Settings also shows an Install AirWallet Online button under As an app.

#Save this page

If you'd rather the page never changed under you, you can keep your own copy. In Settings, under Privacy, select Save this page. It downloads the page as a single file you can open from your disk. That copy works for Bitcoin, Ethereum and Solana; Monero's and Zcash's engines are separate files, so they don't come with it.

#Who the page talks to

The page asks each chain's public servers directly. They see the addresses it asks about, as they would with any wallet.

• Bitcoin: mempool.space and Blockstream (and, if those don't answer, mempool.guide, btcscan.org or Bull Bitcoin's mempool).
• Ethereum: PublicNode (with dRPC, MEV Blocker and 1RPC as fallbacks), and Blockscout for history.
• Solana: PublicNode, or your own Solana server if you set one; Jupiter for token prices.
• Monero: Cake Wallet's node.
• Zcash: zec.rocks, and GitHub for Zcash's one-time Sapling parameter files (checked against their known fingerprints).
• Prices: CoinGecko, only when dollar values are on.

#Limits

• Ethereum's own network only. The page shows Ether and Ethereum tokens on Ethereum itself, not on Base, Arbitrum or the other networks the app supports.
• Solana tokens and activity need your own Solana server (see above).
• No vanity search. Vanity search needs the desktop app or the Chrome extension. See Vanity addresses.
• Watch only. To hold keys, use the AirWallet app.