This is definitely a problem and the best advice is to stay away from free apps. If you've paid for the app upfront it's way less likely to have ads or deceptive in-app purchase stuff. We have a couple apps that use a subscription model that are really high quality — Endless ABCs, ABC Mouse and Homer. You have a pay a couple bucks per month but they have endless amounts of content and educational games, with no ads. tl;dr — get fewer, higher quality apps, pay for the ones you do get, and use them yourself before giving them to your child.
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