dApp
A dApp — decentralized application — is a frontend that interacts with smart contracts on a public blockchain. The UI runs like any web app; the backend is on-chain and permissionless. Uniswap, Aave, and OpenSea are dApps.
How it works
The dApp is typically a static web frontend hosted anywhere. It connects to the user’s wallet via WalletConnect or an injected provider, reads on-chain state through a node RPC, and prompts the wallet to sign transactions that call smart contracts. Because the contracts are public, anyone can build a competing frontend against the same protocol. The dApp itself holds no funds — user assets remain in user wallets or in the on-chain contracts they interact with.
Why it matters
dApps decouple the interface from the settlement layer: a compromised frontend can only trick users into signing bad transactions, not silently drain balances. That is also the risk — most losses in DeFi come from users signing at spoofed or hijacked dApp frontends. Transaction simulation and phishing detection at the wallet layer are the practical defence.
Related concepts
- DEX — A DEX — decentralized exchange — is an on-chain protocol that lets users swap tokens without a central operator holding funds.
- WalletConnect v2 — WalletConnect v2 is an open protocol that lets a wallet on one device connect to a dApp on another — most commonly a mobile wallet paired with a desktop dApp — over an end-to-end-encrypted relay.
- Transaction Simulation — Transaction simulation is a pre-signing check that runs a proposed transaction against a forked node state and reports the expected net asset change to the user before they sign.
- Phishing Site Detection — Phishing site detection is the wallet-level defence that blocks connections to fraudulent domains impersonating legitimate dApps, exchanges, or bridges.
Frequently asked questions
Is a dApp truly decentralized?
The smart-contract backend is; the frontend usually is not. Users should be aware which layer they are trusting.
Do dApps hold my funds?
No — funds either stay in your wallet or are custodied by the on-chain contract you deposit into (a DEX pool, a lending market, etc.).
Can a dApp steal my keys?
It should not have access to them. But a malicious dApp can request signatures that drain approved tokens — hence transaction simulation.
In Veyrnox
Veyrnox connects to dApps via WalletConnect v2 with pre-signing simulation and (on AI Security Protection) live phishing-site checks. See AI Security Protection.