MetaMask is a popular software cryptocurrency wallet used to interact with multiple blockchains, including the Ethereum blockchain. The application allows users to store and manage account keys, broadcast transactions, send and receive Ethereum-based currencies and tokens, and securely connect to decentralized applications through an internet browser.^[1][2]

MetaMask is primarily used through its desktop browser plugin on Chrome and Firefox browsers. In 2020, the mobile version was launched. ^[3][4]

In September 2020, MetaMask hit the 1 million monthly active users milestone.^[5]
In August 2021, it surpassed 10 million monthly active users and became the world's leading non-custodial crypto wallet.^[29]

Overview

MetaMask was originally an extension for accessing Ethereum-enabled distributed applications or "dapps" using popular browsers like Google Chrome. The extension can “read” Ethereum code on any website, providing users with a seamless and accessible tool to interact with various dapps and blockchain products. ^[6]

To get some funds, a user can easily buy Ethereum with a debit card or Apple Pay directly within MetaMask by clicking “Add funds”. They can also request funds from a friend by sending them a payment request showing their QR code in person or by sharing their public address. To transfer existing ETH and tokens to the new MetaMask from another wallet, a user needs to copy their new MetaMask public address and go to their existing wallet or exchange to send funds to their new wallet address.^[7]

Technically, a user does not need any cryptocurrency to use Metamask, they can accept signature requests from sites without any value in an account. However, adding cryptocurrencies in the MetaMask account (such as ETH and ERC-20 or, ERC-721 tokens) allows users to invest, trade, play games, and own unique digital items (NFT collectibles). ^[8]

Every user can sync their MetaMask extension wallet with mobile by using the MetaMask Mobile Sync feature. ^[9]

MetaMask initially supported only ETH and any ETH based token (ERC20, ERC-721, and more). Currently, it supports more than 15 blockchains and tokens created on them, including Binance Smart Chain, Polygon, Avalanche, Fantom , Klaytn, Moonriver Network, Celo, Gnosis and many more. Users can also use a hardware wallet with MetaMask. it supports Trezor and Ledger on the extension, but there is no hardware wallet support on mobile yet. ^[10][30]

In 2018, MetaMask introduced Privacy Mode, an ecosystem-wide standard to improve user privacy on Ethereum. Rather than exposing users’ Ethereum addresses to all sites, Privacy Mode requires that websites ask for user consent before wallets reveal an address. In MetaMask v7.0, this became enabled by default. ^[11]

In July 2019, the team released the Address Book feature, which allows saving nicknames for accounts that are not owned by a user but ones they frequently interact with. ^[12]

In October 2019 at DevCon 5 in Osaka, the MetaMask team presented their new MetaMask Snaps plugin system. With MetaMask Snaps every plugin created has the ability to provide its own API to the sites that a user visits, as well as to other plugins, allowing plugins to build on each other, in a sort of decentralized dependency graph. ^[13]

In July 2020, the team rolled out MetaMask Version 8.^[14]  In September, they launched MetaMask Mobile. ^[15]

In May 2019, MetaMask team reported they reached approximately 264,000 monthly active users. Since that time, it grew over 400%, supporting over one million monthly active users across desktop and mobile apps as of October 2020. The recent launch of MetaMask Mobile played an important role in bringing new users into the MetaMask community. The team noted the top four countries, in order of the volume of mobile users, were the United States, India, Nigeria, and the Philippines. ^[16]

In August 2020, the firm announced MetaMask migrated its open-source code under a new limited license. In a blog post, MetaMask explained that "despite open source software solving critical shared problems, fair compensation for the maintenance of these community goods remains a problem." MetaMask's code was originally published under a permissive MIT license, which enables developers to fork and reuse with very limited restrictions. Its new license, however, seeks to prevent commercial entities from using its software for free. According to MetaMask, the license protects it from "free-riders or upstream competitors from exerting monopolistic control." While the blog post does not specifically name these free-riders or competitors, Jacob Cantele, MetaMask's Head of Product, cited crypto-friendly browser and wallet Brave as an example. "We have to be able to compete with browsers that have forked MetaMask, are pushing their own forks, while also making MetaMask difficult to use (even when explicitly installed)," Cantele explained in a tweet. ^[17]

In September 2020, MetaMask hit the 1 million monthly active users milestone.^[18]

In October 2020, MetaMask team also announced a new feature: token swaps directly within browser extension and mobile application. The token-swapping feature will release first on its Firefox browser extension, before adding extensions for other browsers and MetaMask mobile. MetaMask will seek the best exchange rate for any given trade, accessing all the best-known places to conduct an exchange. The announcement lists services such as Uniswap, Kyber, ParaSwap, 1inch.exchange and DEX.AG. This new service is the latest step in monetizing MetaMask. “There are dynamic fees that range from 0.3% to 0.875% based on order size,” James Beck, a ConsenSys spokesperson, told in a press release. ^[19]

In 2021, Metamask added a feature to view Ethereum NFTs on the Metamask mobile app. The support for NFTs on the desktop version is still in the development.^[31][32]

MetaMask Version 8

MetaMask V8 was announced on July 2, 2020. According to the Medium post with the announcement, this represented a major upgrade to MetaMask and offered a number of new features that no wallet delivered before.

1. Unparalleled Privacy Control. In MetaMask V8, when a user connects to a website, they have the option to select one or more accounts to associate with that website or create a new account just for that site. This new feature enabled users to easily switch between accounts, so they can control which accounts interact with different sites across the decentralized web. If a user opens a site that is not connected to the selected account, MetaMask alerts a user and allows them to connect.
2. New UI. The home screen, asset page, and transaction history were redesigned. Instead of tapping a hamburger icon to view a user's assets, they now access them via the ‘Assets’ tab on the home screen. The ‘Assets’ tab contains a list of the assets a user currently holds and is tracking in MetaMask. There is a possibility to click each asset to view a details page with the transaction history of that asset. The new ‘Activity’ tab is a redesigned transaction history view. With new iconography, each type of transaction is more easily recognizable.
3. Cutting Edge Security. MetaMask's new LavaMoat is a set of tools the team is building that uses Secure EcmaScript to confine every third-party dependency in a piece of JavaScript code at build time.^[20]

MetaMask Mobile

First launched in 2016, MetaMask was only accessible through browser extensions on Google Chrome, Brave, and Firefox and was restricted to mobile users. In October 2019 at Devcon, MetaMask team announced that they were building a mobile application. On July 22, 2019, they released the Public Beta to Android and iOS. Since MetaMask mobile became compatible with open protocols like WalletConnect a user became able to connect to Dapps, such as CryptoKitties, on devices where they didn’t have the extension installed on.^[21][22]

On September 4, 2020, MetaMask team announced the launch of MetaMask Mobile. ^[23]

MetaMask Mobile allows users to have instant and free gasless payments with the use of Payment Channels via Connext. With the exception of user's initial deposit and withdrawal from the payment channel, this feature enables gas-free payments between users. It supports Ethereum mainnet, and Ropsten, Rinkeby, Kovan, Goerli testnets. Mobile apps also has biometrics support - Touch ID, Face ID and Passcode on iOS, Fingerprint/PIN on Android. ^[24]

Controversy

In July 2018, Metamask announced its removal from the Chrome Web Store, the reasons for which were not explained. Several hours later, it was listed again. While MetaMask was delisted, an Ethereum-based prediction market protocol Augur, which earlier got under fire for speculating on death benefits, warned users to not download the MetaMask extension that was actually present in Google Chrome’s store, as it was a fake application. Even though it got listed only few hours after, there never came an explanation for this event. ^[25]

On December 26, 2019, the MetaMask team took to Twitter, where they announced that Google had suspended MetaMask’s Android client from Google Play’s app store, claiming MetaMask was in violation of Google’s financial services policies. Google reportedly cited their policy prohibiting cryptocurrency mining on mobile devices. The MetaMask team attempted to appeal Google’s decision to ban MetaMask from its app store to no avail, as Google promptly rejected the appeal. However, in a tweet posted on January 1 2020, the MetaMask team revealed that:

“Upon careful consideration, Google has permitted The MetaMask mobile app back on the Google Play (Android) store! Thanks to all the believers in an open web for speaking out in our support!” ^[26][27]

MetaMask Snaps

MetaMask has described Snaps as "an open-source system that enables anyone to safely expand the functionality of MetaMask" in order to create new web3 experiences. This means that developers can utilize Snaps to develop specialized features on top of MetaMask.

"The system also allows wallet users to run applications deployed on different networks using MetaMask"^[33]

Snaps aim to provide wallet users with new Web3 experiences and foster a developer ecosystem for building new snaps.

There will be no fees charged to Snaps users by MetaMask. The protocol is scheduled to launch in Q4 of 2023.

Individual snaps are composable, allowing users to build modular snap-stacks that offer tailored functionality. Examples of features supported by snaps include custodying non-Ethereum assets and simulating transactions to safeguard against malicious attacks.

Montoya explained that a snap can provide warnings such as,

"Hey, this contract has been involved in various scams in the past, so you shouldn't interact with it," or "We ran a simulation and discovered that this will transfer all of your USDC."

Team

• Aaron Davis (Kumavis) - Founder
• Dan Finlay - Lead Developer
• Thomas Huang - QA Engineer
• Rachel Cope - Sr. Product Designer
• Dan Miller - Software Engineer
• Randy Brito - Support Engineer
• Erik Marks - Software Engineer
• Jake Haugen - Sr. Product Designer
• Jacob Cantele - Lead of Product & Operations
• Christian Jeria - Sr. Product Designer
• David Pazdan - Technical Support Manager
• Ibrahim Taveras - QA Engineer
• Andre Pimenta - Sr. Software Engineer
• Omna Toshniwal - Product Manager
• Mark Stacey - Software Developer
• Whymarrh Whitby - Software Developer
• Esteban Miño - Software Engineer
• Etienne Dusseault - Software Engineer
• Ricky Miller - Software Developer
• Brad Decker - Software Engineer ^[28]