AdMob integration can happen without Firebase, it’s just a recommendation by Google to use Firebase with it to improve application analysis.
Firebase is mostly free, with the exception of a few functions, such as TestLab, and some functions have a set quota, which comes under the free level, you can definitely use firebase with AdMob, and yes you don’t have to pay anything for free functions and you don’t even need to add a payment method unlike other platforms.
Nayan srivastava
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