This is documentation for the next SDK version. For up-to-date documentation, see the latest version (SDK 54).

Expo TrackingTransparency

GitHub

Changelog

npm

A library for tracking app users and managing tracking permissions.

Android

iOS

tvOS

A library for tracking app users and managing tracking permissions. Provides access to advertising identifiers and manages the required permissions for tracking. Examples of data used for tracking include email address, device ID, advertising ID, and more. If the "Allow Apps to Request to Track" device-level setting is off, this permission will be denied. Be sure to add NSUserTrackingUsageDescription to your Info.plist to explain how the user will be tracked. Otherwise, your app will be rejected by Apple.

For more information on Apple's App Tracking Transparency framework, see their documentation.

Installation

Terminal

- npx expo install expo-tracking-transparency

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-tracking-transparency 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

app.json

{
  "expo": {
    "plugins": [
      [
        "expo-tracking-transparency",
        {
          "userTrackingPermission": "This identifier will be used to deliver personalized ads to you."
        }
      ]
    ]
  }
}

Configurable properties

Name	Default	Description
`userTrackingPermission`	`"Allow this app to collect app-related data that can be used for tracking you or your device."`	Only for: iOS Sets the iOS `NSUserTrackingUsageDescription` permission message in Info.plist.

Are you using this library in an existing React Native app?

If you're not using Continuous Native Generation (CNG) (you're using native android and ios projects manually), then you need to configure following permissions in your native projects:

For Android, add com.google.android.gms.permission.AD_ID permission to your project's android/app/src/main/AndroidManifest.xml.
```
<uses-permission android:name="com.google.android.gms.permission.AD_ID"/>
```

For iOS, add NSUserTrackingUsageDescription key to your project's ios/[app]/Info.plist:

<key>NSUserTrackingUsageDescription</key>
<string>Your custom usage description string here.</string>

Usage

Basic tracking transparency usage

import { useEffect } from 'react';
import { Text, StyleSheet, View } from 'react-native';
import { requestTrackingPermissionsAsync } from 'expo-tracking-transparency';

export default function App() {
  useEffect(() => {
    (async () => {
      const { status } = await requestTrackingPermissionsAsync();
      if (status === 'granted') {
        console.log('Yay! I have user permission to track data');
      }
    })();
  }, []);

  return (
    <View style={styles.container}>
      <Text>Tracking Transparency Module Example</Text>
    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
  },
});

API

import * as ExpoTrackingTransparency from 'expo-tracking-transparency';

Hooks

`useTrackingPermissions(options)`

Android

iOS

tvOS

Parameter	Type
options(optional)	`PermissionHookOptions<object>`

Check or request the user to authorize or deny access to app-related data that can be used for tracking the user or the device. Examples of data used for tracking include email address, device ID, advertising ID, and so on. On iOS, if the user denies this permission, any attempt to collect the IDFA will return a string of 0s.

The system remembers the user’s choice and doesn’t prompt again unless a user uninstalls and then reinstalls the app on the device.

On Android and web, this method always returns that the permission was granted.

Returns:

[null | PermissionResponse, RequestPermissionMethod<PermissionResponse>, GetPermissionMethod<PermissionResponse>]

Example

const [status, requestPermission] = useTrackingPermissions();

Methods

`getAdvertisingId()`

Android

iOS

tvOS

Gets the advertising ID, a UUID string intended only for advertising. Use this string for frequency capping, attribution, conversion events, estimating the number of unique users, advertising fraud detection, and debugging.

As a best practice, don't store the advertising ID. Instead, call this function each time your app needs to use the advertising ID. Users can change whether they allow app tracking and can reset their advertising ID at any time in their system settings. Check your app's authorization using getTrackingPermissionsAsync() to determine the user's intent.

On Android, this function returns the "Android Advertising ID" (AAID). On Android devices that support multiple users, including guest users, it's possible for your app to obtain different advertising IDs on the same device. These different IDs correspond to different users who could be signed in on that device. See Google's documentation for more information: Get a user-resettable advertising ID.

On iOS, this function returns the "Identifier for Advertisers" (IDFA), a string that's unique to each device. Your app must request tracking authorization using requestTrackingPermissionsAsync() before it can get the advertising identifier.

Returns:

string | null

Returns either a UUID string or null. It returns null in the following cases:

On Android, when isLimitAdTrackingEnabled() is true
In the iOS simulator, regardless of any settings
On iOS if you haven't received permission using requestTrackingPermissionsAsync()
On iOS, if you've requested permission and the user declines
On iOS, when a profile or configuration restricts access to the advertising identifier, such as when the user has turned off the system-wide "Allow Apps to Request to Track" setting

Example

TrackingTransparency.getAdvertisingId();
// "E9228286-4C4E-4789-9D95-15827DCB291B"

`getTrackingPermissionsAsync()`

Android

iOS

tvOS

Checks whether or not the user has authorized the app to access app-related data that can be used for tracking the user or the device. See requestTrackingPermissionsAsync for more details.

On Android and web, this method always returns that the permission was granted.

Returns:

Promise<PermissionResponse>

Example

const { granted } = await getTrackingPermissionsAsync();

if (granted) {
  // Your app is authorized to track the user or their device
}

`isAvailable()`

Android

iOS

tvOS

Returns whether the TrackingTransparency API is available on the current device.

Returns:

boolean

On devices where the Tracking Transparency API is unavailable, the get and request permissions methods will always resolve to granted.

`requestTrackingPermissionsAsync()`

Android

iOS

tvOS

Requests the user to authorize or deny access to app-related data that can be used for tracking the user or the device. Examples of data used for tracking include email address, device ID, advertising ID, and so on. On iOS, if the user denies this permission, any attempt to collect the IDFA will return a string of 0s.

The system remembers the user’s choice and doesn’t prompt again unless a user uninstalls and then reinstalls the app on the device.

On Android and web, this method always returns that the permission was granted.

Returns:

Promise<PermissionResponse>

Example

const { granted } = await requestTrackingPermissionsAsync();

if (granted) {
  // Your app is authorized to track the user or their device
}

Types

`PermissionExpiration`

Android

iOS

tvOS

Literal Type: union

Permission expiration time. Currently, all permissions are granted permanently.

Acceptable values are: 'never' | number

`PermissionHookOptions`

Android

iOS

tvOS

Literal Type: union

Acceptable values are: PermissionHookBehavior | Options

`PermissionResponse`

Android

iOS

tvOS

An object obtained by permissions get and request functions.

Property	Type	Description
canAskAgain	`boolean`	Indicates if user can be asked again for specific permission. If not, one should be directed to the Settings app in order to enable/disable the permission.
expires	`PermissionExpiration`	Determines time when the permission expires.
granted	`boolean`	A convenience boolean that indicates if the permission is granted.
status	`PermissionStatus`	Determines the status of the permission.

Enums

`PermissionStatus`

Android

iOS

tvOS

`DENIED`

PermissionStatus.DENIED ＝ "denied"

User has denied the permission.

`GRANTED`

PermissionStatus.GRANTED ＝ "granted"

User has granted the permission.

`UNDETERMINED`

PermissionStatus.UNDETERMINED ＝ "undetermined"

User hasn't granted or denied the permission yet.

Permissions

Android

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

Android Permission	Description
`com.google.android.gms.permission.AD_ID`	Allows access to the Advertising ID for tracking and analytics. Required for apps targeting Android 13 (API level 33) or higher that use Google Play services' Advertising ID.

iOS

The following usage description keys are used by this library:

Info.plist Key	Description
`NSUserTrackingUsageDescription`	A message that informs the user why an app is requesting permission to use data for tracking the user or the device.