Getting started with TypeScript in React Native: Setup, benefits, and best practices

React Native has gained significant attention for building mobile applications that work across platforms with a single codebase.However, as projects scale, managing component props, state types, and API integrations can become challenging. That’s where TypeScript shines.

In this blog, we’ll explore how to integrate TypeScript into a React Native project, understand its benefits, and review best practices with real code examples.

Setting up TypeScript in a React Native project

New Project (React Native 0.71+)
Starting from React Native v0.71, TypeScript is included by default:
npx @react-native-community/cli init MyApp

Adding TypeScript to an Existing Project

Step 1: Install TypeScript and Type Definitions
npm install –save typescript @types/node @types/react @types/react-dom @types/jest @tsconfig/react-native
                                                             OR
yarn add typescript @types/node @types/react @types/react-dom @types/jest @tsconfig/react-native

Step 2: Add a tsconfig.json file

Step 3: Rename files
Rename your files from .js/.jsx to .ts/.tsx depending on whether they contain JSX.

Benefits of using TypeScript in React Native

1. Type Safety
Catch bugs at compile time, not runtime.

2. Better IntelliSense
Your editor can offer accurate auto-completion, inline type hints, and documentation — drastically improving productivity.

3. Improved Code Quality & Documentation
Interfaces and types act as live documentation for your components and APIs.

4. Easier Refactoring
Type checks provide a safety net when renaming props or restructuring logic, reducing the risk of runtime errors.

Best practices for using TypeScript in React Native

1. Define Prop Types with Interfaces

2. Use React.FC with Children Props

3. Avoid the any Type

4. Centralize Types
Create a types/ directory for global types like User, Product, etc.

5.) Use Enums for Constants

TypeScript in Redux

Defining State & Actions

Typing the Reducer

Typing useSelector and useDispatch

TypeScript in React Navigation

Step 1: Define Your Navigation Parameter List
Create a type definition in a types/navigation.ts file:

Step 2: Create the Navigator with Types

Step 3: Access Navigation and Route Props with Proper Typing in Your Screens

Type Operators and Patterns in Interfaces

TypeScript interfaces support several powerful features for building flexible and maintainable types.

1. Union Types (|)
Allows a field to be one of several types.

2. Optional Properties (?)
Makes a property optional.

3. Intersection Types (&)
Combines multiple types or interfaces.

4. Read-only Properties (readonly)
Prevents modification after initialization.

5. Index Signatures ([key: string]: type)
Defines dynamic keys with consistent value types.

6. Function Types in Interface
You can specify a function’s type directly as a property within an interface.

7. Extending Interfaces
You can extend one or more interfaces.

8. Tuple or Array Types in Interfaces

9.) Generic Types in Interface
Interfaces can be generic too:

Example: Advanced ButtonProps Interface

Example: Typed API Call and Component

Interface vs. Type in TypeScript

Both interface and type can be used to define the shape of objects in TypeScript — but they have some key differences and use cases.

Use interface when:

• • You’re defining the structure of objects or classes
  • You want to extend or implement in other interfaces or classes
  • You’re building React props, where interface is commonly preferred

Use type when:

• You need to define unions, intersections, or primitive aliases
• You’re working with function types, tuples, or complex compositions

Example Comparison

Both are valid — and in many basic cases, it’s a matter of preference.

Why Choose TypeScript Over JavaScript?

As your React Native codebase grows, relying on JavaScript can lead to more errors and inconsistencies. TypeScript introduces better structure, safety, and maintainability — which makes it a no-brainer for serious app development.

Bottom line: If you’re working on a growing React Native app, TypeScript is not optional – it’s essential.

Conclusion

Incorporating TypeScript into your React Native project offers numerous advantages – from catching bugs early to improving your development speed and app stability. Whether starting fresh or migrating an existing codebase, even small TypeScript improvements can lead to big wins.

Tip: If you’re migrating an existing project, start small — convert a few components, type the API layer, and grow from there.