Keep Your EVM Assets Secure by Using AirGap Vault

Although software wallets provide easy access, Cold Wallets keep your crypto secure from physical or digital attacks. Your private key is stored offline, so your assets are completely in your control. In this blog, we’ll guide you through how you can use AirGap with any EVM chain, focusing on how you can initiate transactions with popular wallets like MetaMask while signing securely with the AirGap Vault.

AirGap

Published in

AirGap

9 min readMay 9, 2024

Key Takeaways

Ethereum Virtual Machine (or EVM) is a virtual computer that distributes information across the entire Ethereum network. It is responsible for executing smart contracts and updating the state of the blockchain.
EVM is not just for Ethereum; many layer one and two blockchains use it, including Polygon, Binance Smart Chain, Arbitrum and Avalanche.
EVM has improved interoperability and accessibility, powering countless decentralized applications and other use cases across multiple blockchains.
Upgrade your security on EVM chains with AirGap — a free cold wallet solution that allows you to create an airgapped setup for your private keys.
Use Polygon, Binance Smart Chain, Avalanche, Arbitrum and all other EVM-compatible blockchains with AirGap.

You’ve made some profits during the bull run, and now you’re thinking about security. The digital asset market can be volatile, but one thing is always true: keeping your assets safe is crucial. That’s where AirGap comes in — a free, open-source cold wallet solution that gives you peace of mind while securing your Ethereum and EVM-compatible assets.

With AirGap, you can turn a spare device into a secure cold wallet, keeping your private keys offline and away from hackers. It’s easy to set up, user-friendly, and supports not just Ethereum, but all Ethereum Virtual Machine (EVM) chains like Binance Smart Chain, Polygon, and Avalanche.

Ethereum and EVM blockchains

Ethereum shares its underlying technology with other Blockchains that use the Ethereum Virtual Machine (EVM). This technology allows developers to build and run decentralized applications (dApps) on any blockchain that uses EVM, making these blockchains “EVM-compatible.”

Because of this shared technology, Ethereum accounts can interact with all EVM-compatible blockchains in the same way.

It also means that the addresses you use on Ethereum are the same as these other blockchains. So, if you have an Ethereum account, you can use it on chains like Binance Smart Chain, Polygon, Avalanche, and many others without changing a thing.

What does this mean for you?

If you use a Cold Wallet like AirGap to secure your Ethereum account, you can also use it with all these other EVM-compatible blockchains. You can initiate transactions with popular wallets like MetaMask, Rabby Wallet, Blockwallet, or imToken Wallet and then sign them with your cold wallet, which stays offline. This flexibility opens a whole new world of possibilities for interacting with decentralized applications, trading, and more — without compromising security.

Introduction to AirGap

AirGap is an open-source solution that allows you to turn your spare smartphone into a Cold Wallet. It does this by separating the key functions of a wallet into two distinct parts:

AirGap Vault (For signing transactions): This is the Cold Wallet component, it gets installed on a dedicated offline device for maximum security. It securely creates and stores your private keys and is used to sign transactions. Transactions happen with the help of QR code-based signing. This way, Vault maintains a full air gapped state for your private keys. On top of this, AirGap Vault offers a variety of security features like Secure Key generation with Dice Roll/ Coin flip entropy, Social Recovery and Plausible Deniability. To know more about Vault’s features, hop on to AirGap documentation here.

Hot Wallet (For initiating transactions): Common Wallets such as MetaMask, imToken, Rabby Wallet, BlockWallet work with the AirGap Vault and are are responsible for initiating transactions and run on a device that is connected to the internet. The communication between the Hot Wallet and your offline device, that has AirGap Vault installed happens seamlessly via QR codes. This is not only extremely seamleass it also assure that your sensitive data stays physically detached from any online devices. With this setup, you can use any EVM-compatible blockchain with peace of mind. You initiate transactions on your Hot Wallet and then sign them on your offline AirGap Vault, ensuring that your private keys never touch the internet.

For more information about the AirGap solution, you can refer to our documentation.

How to use EVM chains with AirGap — Step-by-step guide

In this guide, we show you how you reach a new level of security by setting up an AirGap Vault, connecting it with MetaMask, and creating a BNB Chain transaction.

Setting up AirGap

If you already have an Ethereum account on AirGap, you can skip this step.

Make sure you have the AirGap Vault app installed. If not, you can download the app from here. The app is available for both Android and iOS devices. We also offer an Android APK to side-load the AirGap Vault on your device. We recommend you install it on a device that is freshly whipped.
Open the app and accept the terms and conditions. Then, choose “Offline S” as your preferred mode. (as a side note, the AirGap Vault can also be installed on an online device if handling smaller funds — ever we recommend using AirGap in an offline setup)

3. After reading all the instructions tap “Generate Secret”. You will be prompted with a permission for your camera and microphone. We recommend you to grant the permission to add additional entropy to ensure that the keys are generated in complete randomness. You can also opt for Dice Roll or Coin Flip Entropy.

4. Read all the instructions carefully and check them all when done. Then, tap on the show recovery phrase button and carefully write down the recovery phrase somewhere safe. It is recommended to back up your Recovery Phrase on stainless steel metal plates. Use the coupon code “BackupEVM” to get 10% on your first order on our AirGap Recovery Plates.

5. Now, you’ll need to verify your recovery phrase. After you are done verifying your recovery phrase, choose a label for it.

6. Now, select Ethereum from the list of accounts and tap Create. Authenticate your secret with your device’s Face ID/Fingerprint or Passcode.

Connecting AirGap with MetaMask

Now that you have set up an Ethereum account, its time to connect it with a Hot Wallet. In this guide we will go with MetaMask as it is the most used Hot Wallet among EVM users.

Make sure you already have a MetaMask account set in the extension/application.
Go to MetaMask and tap on your profile circle. Then, select Connect Hardware Wallet.

3. Then, select QR based wallets and hit Continue. It will ask you to scan a QR code.

4. Now open the Vault app and select the Ethereum account that we just created. Select MetaMask from the list of supported wallets. You’ll get the QR code. Scan it with your MetaMask extension.

5. Now, select the account that you want to connect. Carefully check the public address of the account that you created and select that account. Most probably, that will be the first account from the list.

6. Now, open the MetaMask extension’s home page and check your connected account.

Adding and using EVM-chains

Now that you have connected the Ethereum account to MetaMask, it’s time for you to add your favorite EVM chain. In this guide, we will go with Binance Smart Chain.

First, tap on the Ethereum icon on MetaMask. Check if Binance Smart Chain is listed there. If not, hit Add Network.

2. You’ll see some EVM-compatible networks. Choose Binance Smart Chain from the list and hit Add. If you want to add an EVM chain that’s not on the list, you can add it manually as well.