What is the best way to organize free and paid receipt of new features in an iOS app?

Question

iOS

Tell me, please, iOS developers, how best to organize free and paid receipt of new features in an iOS application?
Example:
there is a free game, some of the new released levels are supposed to be delivered free of charge, and some are paid.
Does it make sense to reinvent your wheel, with downloading from your server, with your own mechanisms, or are there mechanisms for organizing free and paid "purchases" in the application, directly from Apple?
I know about in-app purchases, of course, but we are talking about free and paid updates. Is it enough for free downloads to simply set a price of zero?
Thanks for the advice!

Answer 1

As an option, get free levels along with the update, and paid ones through an in-app purchase.

Answer 2

You can get confused for loading new levels. But it's better to do everything through updates of the entire application.

Answer 3

There is no zero price for in-app purchases. Therefore, all free features (including levels) will have to be delivered using updates of the entire application. For paid levels, you can make in-app purchases and download from your server. In this case, it seems like you can add new levels without an update.