Web3 wallet
A crypto wallet that manages keys and signs transactions — MetaMask, Phantom, Coinbase Wallet. Wallets are how users interact with blockchains (send crypto, use DeFi, mint NFTs). Browser extensions or mobile apps. Your keys, your crypto.
- Interacting with any blockchain/dApp.
- Holding crypto assets.
- Signing blockchain transactions.
- DeFi, NFTs, DAO participation.
- When you don't need blockchain (use traditional auth).
- When security can't be managed (use custodial).
- When UX simplicity is critical.
Definition
A web3 wallet stores private keys and signs transactions. MetaMask (Ethereum), Phantom (Solana), Coinbase Wallet are popular. Browser extensions inject window.ethereum; mobile apps use WalletConnect. HD wallets derive keys from a seed phrase. Hardware wallets (Ledger) are the most secure.
Why it exists
Blockchains are public ledgers — you need a way to prove ownership and sign transactions. Wallets manage keys securely and let users interact with dApps.
How it works
Wallet generates a seed phrase → derives private keys → addresses. To use a dApp, connect your wallet (it injects a provider). dApp requests a signature → wallet shows you what to sign → you approve → it broadcasts to the blockchain. Keys never leave the wallet.
Scaling limits
Seed phrase loss = total loss. Phishing attacks target wallet users. UX is complex for beginners. Transaction fees (gas). Different wallets for different chains.
Cost shape
Free to create/use (you pay gas fees). Hardware wallets cost $50-200.
Alternatives
- Custodial wallets (Coinbase app) — Easier, but you don't control keys.
- Smart contract wallets (Safe) — More features, more complex.
- Hardware wallet — Most secure, less convenient.
Failure modes
- Seed phrase loss.
- Phishing.
- Malicious signature requests.
- UX complexity.
- Gas fees.