React Native enables JavaScript developers to build native mobile applications using familiar web development paradigms. Unlike hybrid approaches that render web views, React Native compiles to actual native components, delivering performance closer to fully native applications. Understanding React Native’s architecture helps developers make informed decisions and build applications that perform well on both iOS and Android.

Understanding the Architecture

React Native consists of three main threads that communicate through a bridge mechanism. The JavaScript thread runs your application logic and React rendering decisions. The Native thread handles UI rendering using platform-native components. The Shadow thread calculates layout using Yoga, a cross-platform layout engine.

The bridge serializes data between JavaScript and native code as JSON messages. This asynchronous communication enables non-blocking UI updates but introduces latency for operations requiring round trips between threads. Understanding when and how bridge communication occurs is essential for performance optimization.

The New Architecture, introduced in React Native 0.68, replaces the bridge with JavaScript Interface (JSI), enabling synchronous communication between JavaScript and native code. Fabric, the new rendering system, enables concurrent rendering features similar to React 18. TurboModules provide lazy loading of native modules. These improvements significantly enhance performance for demanding applications.

Project Structure and Organization

Well-organized React Native projects separate concerns clearly, enabling teams to navigate codebases efficiently and make changes confidently.

src/
├── api/                    # API client and endpoint definitions
│   ├── client.ts
│   ├── endpoints/
│   └── types/
├── components/             # Reusable UI components
│   ├── common/
│   ├── forms/
│   └── layout/
├── features/               # Feature-based modules
│   ├── auth/
│   │   ├── components/
│   │   ├── hooks/
│   │   ├── screens/
│   │   └── store/
│   ├── products/
│   └── orders/
├── hooks/                  # Shared custom hooks
├── navigation/             # Navigation configuration
├── store/                  # Global state management
├── theme/                  # Styling and theming
├── types/                  # TypeScript type definitions
└── utils/                  # Utility functions

State Management Approaches

React Native applications can use any React state management solution. The choice depends on application complexity, team familiarity, and specific requirements.

React Context works well for simple global state like themes, authentication status, and user preferences. It requires no additional dependencies and integrates naturally with React components.

Redux remains popular for complex applications with significant global state. Redux Toolkit simplifies configuration and reduces boilerplate. RTK Query handles API caching and synchronization elegantly.

Zustand offers a simpler alternative to Redux with less boilerplate and excellent TypeScript support. Its hook-based API feels natural to React developers.

// Zustand store example
import { create } from 'zustand';
import { persist, createJSONStorage } from 'zustand/middleware';
import AsyncStorage from '@react-native-async-storage/async-storage';

interface CartState {
  items: CartItem[];
  addItem: (product: Product, quantity: number) => void;
  removeItem: (productId: string) => void;
  updateQuantity: (productId: string, quantity: number) => void;
  clearCart: () => void;
  total: () => number;
}

export const useCartStore = create<CartState>()(
  persist(
    (set, get) => ({
      items: [],
      
      addItem: (product, quantity) => set((state) => {
        const existing = state.items.find(i => i.productId === product.id);
        if (existing) {
          return {
            items: state.items.map(i =>
              i.productId === product.id
                ? { ...i, quantity: i.quantity + quantity }
                : i
            ),
          };
        }
        return {
          items: [...state.items, {
            productId: product.id,
            name: product.name,
            price: product.price,
            quantity,
          }],
        };
      }),
      
      removeItem: (productId) => set((state) => ({
        items: state.items.filter(i => i.productId !== productId),
      })),
      
      updateQuantity: (productId, quantity) => set((state) => ({
        items: quantity > 0
          ? state.items.map(i =>
              i.productId === productId ? { ...i, quantity } : i
            )
          : state.items.filter(i => i.productId !== productId),
      })),
      
      clearCart: () => set({ items: [] }),
      
      total: () => get().items.reduce(
        (sum, item) => sum + item.price * item.quantity,
        0
      ),
    }),
    {
      name: 'cart-storage',
      storage: createJSONStorage(() => AsyncStorage),
    }
  )
);

Navigation Patterns

React Navigation is the standard navigation library for React Native. It provides stack, tab, and drawer navigators that render native navigation components on each platform.

// Navigation setup with TypeScript
import { NavigationContainer } from '@react-navigation/native';
import { createNativeStackNavigator } from '@react-navigation/native-stack';
import { createBottomTabNavigator } from '@react-navigation/bottom-tabs';

type RootStackParamList = {
  Main: undefined;
  ProductDetails: { productId: string };
  Checkout: undefined;
  OrderConfirmation: { orderId: string };
};

type MainTabParamList = {
  Home: undefined;
  Search: undefined;
  Cart: undefined;
  Profile: undefined;
};

const Stack = createNativeStackNavigator<RootStackParamList>();
const Tab = createBottomTabNavigator<MainTabParamList>();

function MainTabs() {
  return (
    <Tab.Navigator
      screenOptions={({ route }) => ({
        tabBarIcon: ({ focused, color, size }) => {
          return <TabIcon name={route.name} focused={focused} size={size} color={color} />;
        },
      })}
    >
      <Tab.Screen name="Home" component={HomeScreen} />
      <Tab.Screen name="Search" component={SearchScreen} />
      <Tab.Screen name="Cart" component={CartScreen} />
      <Tab.Screen name="Profile" component={ProfileScreen} />
    </Tab.Navigator>
  );
}

export function AppNavigator() {
  return (
    <NavigationContainer>
      <Stack.Navigator>
        <Stack.Screen 
          name="Main" 
          component={MainTabs} 
          options={{ headerShown: false }}
        />
        <Stack.Screen 
          name="ProductDetails" 
          component={ProductDetailsScreen}
          options={{ title: 'Product' }}
        />
        <Stack.Screen name="Checkout" component={CheckoutScreen} />
        <Stack.Screen 
          name="OrderConfirmation" 
          component={OrderConfirmationScreen}
          options={{ headerBackVisible: false }}
        />
      </Stack.Navigator>
    </NavigationContainer>
  );
}

Performance Optimization

React Native performance optimization focuses on reducing bridge traffic, optimizing renders, and leveraging native capabilities appropriately.

Memoization prevents unnecessary re-renders. Use React.memo for components that receive stable props. Use useMemo for expensive calculations and useCallback for callback functions passed to child components.

FlatList optimizes long lists through virtualization, rendering only visible items. Configure getItemLayout when item heights are fixed. Use keyExtractor for stable keys. Avoid inline functions and objects in renderItem.

const ProductList = ({ products, onProductPress }) => {
  const renderItem = useCallback(({ item }) => (
    <ProductCard 
      product={item} 
      onPress={() => onProductPress(item.id)}
    />
  ), [onProductPress]);
  
  const keyExtractor = useCallback((item) => item.id, []);
  
  const getItemLayout = useCallback((data, index) => ({
    length: ITEM_HEIGHT,
    offset: ITEM_HEIGHT * index,
    index,
  }), []);
  
  return (
    <FlatList
      data={products}
      renderItem={renderItem}
      keyExtractor={keyExtractor}
      getItemLayout={getItemLayout}
      initialNumToRender={10}
      maxToRenderPerBatch={10}
      windowSize={5}
      removeClippedSubviews={true}
    />
  );
};

Animations should run on the native thread when possible. React Native Reanimated provides worklets that execute animations without bridge communication. This enables smooth 60fps animations even during JavaScript thread blocking.

Native Module Integration

React Native applications can access native platform capabilities through native modules. When JavaScript libraries are insufficient, write native code and expose it to JavaScript.

TurboModules in the New Architecture provide type-safe native module interfaces with lazy loading. Codegen generates native code from TypeScript specifications, ensuring type consistency across the bridge.

// TypeScript specification for TurboModule
import type { TurboModule } from 'react-native';
import { TurboModuleRegistry } from 'react-native';

export interface Spec extends TurboModule {
  getBatteryLevel(): Promise<number>;
  getDeviceInfo(): {
    model: string;
    osVersion: string;
    appVersion: string;
  };
  vibrate(pattern: number[]): void;
}

export default TurboModuleRegistry.getEnforcing<Spec>('DeviceModule');

Testing Strategies

React Native testing combines JavaScript testing tools with platform-specific testing approaches.

Unit tests with Jest verify component logic and utility functions. React Native Testing Library renders components and enables querying by accessibility properties.

import { render, fireEvent, waitFor } from '@testing-library/react-native';
import { ProductCard } from './ProductCard';

describe('ProductCard', () => {
  const mockProduct = {
    id: '1',
    name: 'Test Product',
    price: 29.99,
    imageUrl: 'https://example.com/image.jpg',
  };
  
  it('displays product information', () => {
    const { getByText } = render(
      <ProductCard product={mockProduct} onPress={() => {}} />
    );
    
    expect(getByText('Test Product')).toBeTruthy();
    expect(getByText('$29.99')).toBeTruthy();
  });
  
  it('calls onPress when pressed', () => {
    const onPress = jest.fn();
    const { getByTestId } = render(
      <ProductCard product={mockProduct} onPress={onPress} />
    );
    
    fireEvent.press(getByTestId('product-card'));
    expect(onPress).toHaveBeenCalledTimes(1);
  });
});

Conclusion

React Native provides a compelling path to cross-platform mobile development for teams with JavaScript expertise. The New Architecture addresses historical performance limitations, making React Native viable for increasingly demanding applications.

Success with React Native requires understanding its architecture, optimizing for its specific performance characteristics, and knowing when native code provides better solutions. The patterns covered here provide a foundation for building performant, maintainable React Native applications.

At RyuPy, we evaluate each project’s requirements to determine whether React Native’s cross-platform benefits outweigh native development advantages. For the right projects, React Native enables rapid development without sacrificing user experience.