Polkadex is a decentralized cryptocurrency exchange built on the Substrate platform. It offers non-custodial peer-to-peer trading, high-frequency trading, and advanced trading tools. The platform aims to provide a fast and cost-effective trading experience with a sleek user interface. Polkadex utilizes a Layer 2 trusted execution environment and a bridge for interoperability with other blockchains. It also offers a decentralized IDO platform called PolkaIDO. Users can stake the PDEX token and earn passive income.