[Help] Issues integrating AdMob with Expo (Kotlin version conflict)

Hey folks! I'm building a simple study app using Expo, starting from a completely blank template. The only thing I’ve added so far is an AdMob banner component using react-native-google-mobile-ads. Here's what I did: Created a blank Expo app Added a basic Banner component Imported: import { BannerAd, BannerAdSize, TestIds } from 'react-native-google-mobile-ads'; And passed the correct banner ID. Added this to my app.json: "react-native-google-mobile-ads": { "android_app_id": "xxxxxxxxxxxxxxxxxxxxxxx", "ios_app_id": "xxxxxxxxxxxxxxxxxxxxxxx" } Then I ran: npx expo run:android And boom - got hit with a Kotlin version error: kotlin_moduleModule was compiled with an incompatible version of Kotlin. `The binary version of its metadata is 2.1.0, expected version is 1.9.0. Task :react-native-google-mobile-ads:compileDebugKotlin FAILED` I tried changing the Kotlin version in build.gradle to 2.1.0, but that opened up a whole new can of worms with more errors. I also tried using expo-build-properties to set Kotlin versions, but still no luck. Has anyone managed to get AdMob working with a recent Expo setup? Any working guides or examples would be super appreciated. Current versions: "expo": "~52.0.43" "react": "18.3.1" "react-native": "0.76.9" "react-native-google-mobile-ads": "^15.0.0" Thanks in advance!

Apr 5, 2025 - 16:25

[Help] Issues integrating AdMob with Expo (Kotlin version conflict)

Hey folks!

I'm building a simple study app using Expo, starting from a completely blank template. The only thing I’ve added so far is an AdMob banner component using react-native-google-mobile-ads.

Here's what I did:

Created a blank Expo app

Added a basic Banner component

Imported:

import { BannerAd, BannerAdSize, TestIds } from 'react-native-google-mobile-ads';

And passed the correct banner ID.

Added this to my app.json:

"react-native-google-mobile-ads": { "android_app_id": "xxxxxxxxxxxxxxxxxxxxxxx", "ios_app_id": "xxxxxxxxxxxxxxxxxxxxxxx" }

Then I ran:

npx expo run:android
And boom - got hit with a Kotlin version error:

kotlin_moduleModule was compiled with an incompatible version of Kotlin. `The binary version of its metadata is 2.1.0, expected version is 1.9.0.

Task :react-native-google-mobile-ads:compileDebugKotlin FAILED`
I tried changing the Kotlin version in build.gradle to 2.1.0, but that opened up a whole new can of worms with more errors. I also tried using expo-build-properties to set Kotlin versions, but still no luck.

Has anyone managed to get AdMob working with a recent Expo setup? Any working guides or examples would be super appreciated.

Current versions:

"expo": "~52.0.43" "react": "18.3.1" "react-native": "0.76.9" "react-native-google-mobile-ads": "^15.0.0"

Thanks in advance!