Apscan

Ferum is an on-chain order book on Aptos that stands out for its developer-friendly features. It provides a platform that is easy to navigate and use, making it an ideal choice for developers working with Aptos.

Wing Finance is a credit-based, cross-chain DeFi platform. The content from this URL could not be retrieved, so I'm unable to provide a detailed introduction.

StarSwap is a full-featured decentralized exchange (DEX) on Aptos and Starcoin. It allows developers, traders, and liquidity providers to participate in a financial marketplace that is open and accessible to all. Users can freely exchange tokens on StarSwap and become automated market makers by providing and staking liquidity.