There will probably be AI operating systems of some kind in the near future. I don't really know what that means, but whenever we get there I would really like there to be case law that forces monopolist OS developers to allow free trade when it comes to the application layer.

I don’t care about the 90% of App Store revenue that comes in app purchases in games (came out in the trial).

I do care about subscription services where at most there should be a one time finders fee and then maybe a slightly higher monthly fee for payments like 5% instead of just enough to cover the processing fees.

Also, I just checked out the Kindle app for iOS. There is a link to the book that takes you to the Amazon web site to let you buy the book directly with one (well two clicks) in all. A much better user experience.