Google Ads are not an integrated part of any Android OS. Google Play Store is available on most western Android phones but is not part of an OS - see Amazon Kindle and most Chinese phones.
Google ads are delivered either via web pages or as ads in apps. In both cases the owner of the page/app decides which ad network they'll use. There is plenty of competition in ads space.
The situation is the same on iOS, where Google has no leverage, yet they have the same revenue stream from ads.
The only advantage Google has is the default search engine setting on official Google Android phones.
Google ads are delivered either via web pages or as ads in apps. In both cases the owner of the page/app decides which ad network they'll use. There is plenty of competition in ads space.
The situation is the same on iOS, where Google has no leverage, yet they have the same revenue stream from ads.
The only advantage Google has is the default search engine setting on official Google Android phones.
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