CEX vs DEX vs wallet apps — Key concepts

CEXA company holds the private keys. Trades are instant inside their database; on-chain movement happens only when you deposit or withdraw. You log in with email/2FA and accept their rules.

Cryptography is about how to maintain control over information.

— Shafi Goldwasser

DEXYou hold the keys (MetaMask, Rabby, Coinbase Wallet). Trades run through smart contracts on-chain. You pay gas, choose slippage, and sign every step.

Wallet appsThe interface for your keys and signatures. Some have built-in swaps that route to a DEX behind the scenes; fees still show as gas + protocol fee.

Same principles across wallets: confirm the network, confirm the spender/contract, and read the fee line before you sign.