You must first enable user metrics in your AdMob account before you can link your AdMob apps to Firebase . Firebase is a development platform for mobile and web apps. With Firebase, you can quickly build high-quality apps, grow an engaged user base, and earn more money.
Read moreHow do I add AdMob to Firebase?
Sign in to your AdMob account at https://apps.admob.com.
Read moreHow do I start AdMob on my Android app?
Programming part — XML attributes
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