Amen! This article stressed the importance content management. Another consideration is the premium upgrade. It makes sense to allow the user to test the basic features and get the feel for the app — but some go too far.
I once deleted app that had so many ads that it rendering the app unusable. Then offered a free upgrade if i rated the app 5 stars — nothing like annoying the user into upgrading.
Another consideration is the how and where. A running app I used kept having ads pop up during critical moments — a dangerous situation for users running on roads with car traffic.