expo-device-check

Expo module that exposes the native DeviceCheck API on iOS. It mirrors the simple API of react-native-device-check while integrating with Expo's module system.

DeviceCheck is available only on physical iOS devices running iOS 11 or later. Calls made from a simulator will fail.

Installation

npx expo install expo-device-check

If your project uses the Expo prebuild workflow, remember to run expo prebuild (or npx pod-install inside the ios directory) after installing the package.

Usage

import DeviceCheck from 'expo-device-check';
// or: import { getDeviceToken, isSupported } from 'expo-device-check';

async function loadToken() {
  if (!DeviceCheck.isSupported) {
    throw new Error('DeviceCheck is not supported on this device.');
  }

  try {
    const token = await DeviceCheck.getDeviceToken();
    // send token to your backend for attestation
  } catch (error) {
    console.error('Failed to fetch DeviceCheck token', error);
  }
}

API

Method	Description
DeviceCheck.getDeviceToken(): Promise<string>	Generates a base64-encoded DeviceCheck token.
DeviceCheck.isSupported: boolean	Indicates whether the current device can use DeviceCheck.

Error handling

getDeviceToken throws an ERR_EXPO_DEVICE_CHECK_* error when the API is unavailable (e.g. simulator, iOS version < 11) or when token generation fails.

Apple privacy manifest

Because this module calls DCDevice, your app must declare the appropriate usage reason codes in its PrivacyInfo.xcprivacy. Expo does not automatically add these declarations, so update your app's privacy manifest accordingly before submitting to the App Store.

Development

npm install
npm run build

This repository intentionally only implements the iOS DeviceCheck API. Calls on other platforms will throw an UnavailabilityError.

License

MIT