MobX Developer Tools is a free Chrome add-on designed for developers using MobX with React. This tool provides essential functionalities to inspect mobx-react observers, allowing users to view and edit values within observable objects. It's important to note that while this tool focuses on MobX, it does not support editing React props or state—developers are encouraged to use react-devtools for those purposes.

Additionally, MobX Developer Tools enables tracking changes in MobX observables, making it easier to manage state in applications. The tool also offers support for MobX State Tree (MST), further enhancing its utility for developers who require a robust solution for managing complex state in their applications. Overall, this add-on is a valuable resource for anyone looking to streamline their MobX development process.