---
title: Get started
---

import { BoxLink } from '~/ui/components/BoxLink';
import { Terminal } from '~/ui/components/Snippet';

There are two ways to get started with the Expo Module API: you can either initialize a new module from scratch or add the Expo Module API to an existing module.
This guide will walk you through creating a new module from scratch, and the ["Integrating in an existing library" guide](/modules/existing-library) covers the latter case.

## 1. Creating a new module

To create a new Expo module from scratch, run the `create-expo-module` script as shown below.
The script will ask you a few questions and then generate the native Expo module along with the example app for Android and iOS that uses your new module.

<Terminal cmd={[`$ npx create-expo-module my-module`]} />

## 2. Running the example project

Navigate to the module directory and then open the Android and/or iOS example project by running the following commands:

<Terminal cmd={[`$ cd my-module`, `$ npm run open:android`, `$ npm run open:ios`]} />

Now, you can run the example project on your device or simulator/emulator. When the project compiles and runs, you will see "Hello world! 👋" on the screen.

> **Note:** If you're using Windows, you can open the example project by opening the `android` directory in Android Studio, but you cannot open the iOS project files.

## 3. Making a change

### Android

Open up **MyModuleModule.kt** in Android Studio (<kbd>⌘ Cmd</kbd> + <kbd>O</kbd> or <kbd>Ctrl</kbd> + <kbd>O</kbd> and search for **MyModuleModule.kt**).
Change the `hello` method to return a different string.
For example, you can change it to return `"Hello world! 🌎🤖"`. Rebuild the app and you should see your change.

### iOS

Open up **MyModuleModule.swift** in Xcode (<kbd>⌘ Cmd</kbd> + <kbd>O</kbd> or <kbd>Ctrl</kbd> + <kbd>O</kbd> and search for **MyModuleModule.swift**).
Change the `hello` method to return a different string.
For example, you can change it to return `"Hello world! 🌎🍎"`. Rebuild the app and you should see your change.

## Next steps

Now that you've learned how to initialize a module and make simple changes to it, you can continue to a tutorial or dive right into the API reference.

<BoxLink
  title="Creating your first native module"
  description="Create a simple, but complete, native module to interact with Android and iOS preferences APIs."
  href="/modules/native-module-tutorial"
/>

<BoxLink
  title="Module API Reference"
  description="Outline for the Expo Module API and common patterns like sending events from native code to JavaScript."
  href="/modules/native-module-tutorial"
/>