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expo-local-authentication allows you to use the Biometric Prompt (Android) or FaceID and TouchID (iOS) to authenticate the user with a fingerprint or face scan.

Known limitation

iOS 

iOS

The FaceID authentication for iOS is not supported in Expo Go. You will need to create a development build to test FaceID.

Installation

If you are installing this in an existing React Native app, make sure to install expo in your project.

Configuration in app config

You can configure expo-local-authentication using its built-in config plugin if you use config plugins in your project (Continuous Native Generation (CNG)). The plugin allows you to configure various properties that cannot be set at runtime and require building a new app binary to take effect. If your app does not use CNG, then you'll need to manually configure the library.

Example app.json with config plugin

{
  "expo": {
    "plugins": [
      [
        "expo-local-authentication",
        {
          "faceIDPermission": "Allow $(PRODUCT_NAME) to use Face ID."
        }
      ]
    ]
  }
}

Configurable properties

<key>NSFaceIDUsageDescription</key>
<string>Allow $(PRODUCT_NAME) to use FaceID</string>

API

import * as LocalAuthentication from 'expo-local-authentication';

No API data file found, sorry!

Permissions

Android

The following permissions are added automatically through this library's AndroidManifest.xml:

iOS

The following usage description keys are used by this library: