Performance is one of the most critical aspects of mobile app development. To ensure smooth user experiences in 2024, developers must implement performance optimization techniques in React Native and Flutter apps. Code-splitting helps reduce the initial load time by only loading essential components upfront, while lazy loading defers non-critical resources until they're needed. In React Native, minimizing the use of unnecessary re-renders, optimizing JavaScript threads, and using native modules for intensive tasks are crucial. For Flutter, using efficient widgets and limiting heavy computation on the UI thread ensures better performance. Profiling tools like React DevTools and Dart DevTools can also help identify bottlenecks in the app's performance and guide further optimization.