'RNGoogleMobileAdsModule' Error in React Native/Expo and Solutions

I have been developing an application with Expo using React Native for a while now. I would like to share an error I encountered and its solutions in this blog post. One of the most common errors encountered during AdMob integration in React Native projects, especially if you are using Expo, is as follows:

TurboModuleRegistry.getEnforcing(...): 'RNGoogleMobileAdsModule' could not be found. Verify that a module by this name is registered in the native binary.

I started seeing this error when I wanted to add Google Admob to my project. I wanted to add a banner ad just above the bottom tab in my project. After doing some research, the react-native-google-mobile-ads library caught my eye again. I had used it in a different project before and it worked. But at that time, I had not used Expo Router in my project.

I have not yet been able to solve this error on emulator devices, but it works on physical devices. I think the problem is caused by Expo Router. This error occurs when the library is not properly integrated into the project or due to Expo’s working limitations. In this article, I will discuss the causes of this error and its solutions in detail.

React Native App Development Error “RNGoogleMobileAdsModule”

Expo Go Limitations: Expo Go app does not support native modules like AdMob. A custom development build must be created in order for these modules to work.

Incorrect Module Installation: The react-native-google-mobile-ads library may not have been loaded and linked correctly.

Missing Native Connections: Necessary settings may not have been made on the Android and iOS native side.

Possible Solutions I’ve Tried

Creating a Custom Development Build

To use native modules like AdMob, you need to create a special development build instead of the standard Expo Go. To do this, run these commands:

eas build --profile development --platform android

This will create an app that includes the react-native-google-mobile-ads module. You can test it by installing the generated APK or IPA file on your device.

Add Correct AdMob Configuration

Make sure your app.json or app.config.js file is configured correctly:

{
  "expo": {
    "plugins": [
      [
        "react-native-google-mobile-ads",
        {
          "android_app_id": "ca-app-pub-xxxxxxxxxxxxxxxx~xxxxxxxxxx", // Gerçek App ID'nizi girin
          "ios_app_id": "ca-app-pub-xxxxxxxxxxxxxxxx~xxxxxxxxxx"
        }
      ]
    ]
  }
}

After making changes:

expo prebuild

Install and Connect the Module Properly

If you need to manually link native modules in the project, follow these steps:

npm install react-native-google-mobile-ads

Install Pod files for iOS:

npx pod-install

Add AdMob Banner Correctly

To add AdMob banners to tab screens, edit your _layout.tsx file as follows:

import React from "react";
import { View, StyleSheet, Platform } from "react-native";
import { Tabs } from "expo-router";
import { BannerAd, BannerAdSize, TestIds } from "react-native-google-mobile-ads";

const adUnitId = __DEV__
  ? TestIds.BANNER
  : "ca-app-pub-xxxxxxxxxxxxxxxx/xxxxxxxxxx"; // Gerçek reklam ID'sini girin

export default function TabLayout() {
  return (
    <View style={{ flex: 1 }}>
      <Tabs
        screenOptions={{
          tabBarActiveTintColor: "blue",
          tabBarInactiveTintColor: "gray",
        }}
      />
      {Platform.OS !== "web" && (
        <BannerAd
          unitId={adUnitId}
          size={BannerAdSize.BANNER}
          requestOptions={{
            requestNonPersonalizedAdsOnly: true,
          }}
        />
      )}
    </View>
  );
}

Clear Expo Cache

If the problem persists after the configuration, clear the Expo cache:

expo start --clear

“TurboModuleRegistry.getEnforcing(…): ‘RNGoogleMobileAdsModule’ could not be found. Verify that a module by this name is registered in the native binary.” error is a common problem encountered during AdMob integration in Expo projects. Creating a custom development build and ensuring the correct configuration is the main way to resolve this error. By following the above steps, you can use AdMob banner ads in your application without any problems.