Integrating Firebase with a React app is a pivotal step when developing a Playstore clone app, as Firebase offers a comprehensive suite of backend services crucial for modern app development. Firebase Config, which includes API keys and other configuration details, is essential for initializing Firebase services within your React app. By integrating Firebase, developers can leverage real-time databases, authentication, cloud storage, and analytics, all of which are necessary for a robust Playstore clone. This setup facilitates seamless user authentication, efficient data management, and real-time updates, ensuring that the app functions smoothly and securely.