React Native for Web is an extension of React Native that allows developers to use React's components and APIs to create applications for web, Android, and iOS platforms from a single codebase. It translates React Native APIs like View into their HTML5 counterparts, facilitating the development of web applications that closely mirror their native counterparts. While popular on GitHub and NPM, React Native for Web has limitations such as restricted web API support, missing core components, styling issues, and compatibility challenges with certain libraries. It is best suited for projects where the web and native apps have similar functionalities. Alternatives include using Solito for navigation or creating separate libraries for web and mobile. Expo is a recommended toolchain for getting started with React Native for Web, with options for new projects or migrating existing ones. Despite its limitations, React Native for Web remains a popular choice for developers seeking to unify their app development process across multiple platforms.