MyEtherWallet

MyEtherWallet (MEW) is a highly respected, deeply historically significant titan that was the absolute mathematical foundation of the Ethereum ecosystem before MetaMask exploded. It was the first platform that allowed normal humans to interact with Ethereum Smart Contracts. Today, it remains an incredibly powerful, open-source, client-side interface that provides terrifyingly deep, granular control over the Ethereum blockchain. Its absolute biggest differentiator is "The Client-Side Raw Contract Interface." While MetaMask abstracts the blockchain behind a UI, MEW allows developers and power users to mathematically inject raw hexadecimal data directly into the Ethereum blockchain. A user can paste a Smart Contract's ABI (Application Binary Interface) directly into MEW, and manually trigger complex mathematical functions on decentralized protocols that do not even have a website UI yet. Because it is an interface, its "Hardware Wallet Gateway" is legendary. MEW is not a traditional app that holds keys. It is an open-source website that mathematically runs locally in your browser. You plug your Ledger, Trezor, or KeepKey into your computer, and MEW mathematically acts as the visual dashboard, allowing you to sign offline transactions and broadcast them to the Ethereum network with absolute, uncompromised cold-storage security.