Worth noting that unless you’re personally selling advertising (which only a few people can do), ads are subject to a fee as well, by the broker/network. You

Worth noting that unless you’re personally selling advertising (which only a few people can do), ads are subject to a fee as well, by the broker/network. You don’t collect 100% of the money paid by the advertiser. What you avoid with ads on iOS is paying twice: Once to the broker, and again to Apple.