We've recently released an app on iOS that has ads and is aimed at a younger audience. We have an option to remove the ads and it comes with an added ability to put a childlock on in app messaging. Later when we add a store into the app we will add features to lock it further because we want to do right by our customers who we hope include parents of kids.

What I didn't expect was the slump in sales we make from ad removal offerings. We make more money from the ads than from purchases of ad removal. I see a lot of folks say "I'll pay for a no ads experience" but the reality is most folks will continue to use the app with the ads even when the option to remove them exists.

Adding code to handle ad removal is another feature which takes time to develop and keep up to date as APIs and system versions change. Sadly, it may not be lucrative enough for most developers to put that effort in to provide the option.