The backend choice for React Native comes down to personal preference. If you are looking for something lightweight and flexible, then Node.js is your best bet. It offers scalability, great extensibility, and a wide range of tools to help developers build custom solutions quickly and efficiently. Another option is Firebase, which provides out-of-the-box features such as real-time data synchronization, an easy-to-use database system, cloud storage for media files, and authentication support - all without needing any server or computation setup! To sum it up: if you want the freedom of full customization with no hassle - go with Node.js; if you need an all-in-one solution without lifting much of a finger (but also limited control) - go with Firebase.