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I wasn't sure how to title the question, but my situation is:I have a web solution with some free features and a packege of features which can be purchased together via single subscription. Let's say that subscription is 100 USD. I have an iOS app at AppStore which is 100% free, with all free features, but I would like to add a feature which is a part of the previously mentions subscription package, so it is visible and can be used inside mobile app only when a user has paid subscription on web portal. Do I need to implement IAP for that feature and if I need to, which price should I define? 100 USD since it is a part of package and it is the easiest solution, or for example 30 USD because it is only a single feature, but it requires changes on backend side related to subscriptions/purchasing handling?Thanks in advance

I have a specific problem. I've published a free application on AppStore. Now, I want to add a new feature which is a part of a complex subscription system, and this feature should be hidden by default, i.e. visible only to users who already have subscription paid on our web portal. There should be no link inside the app which asks the user to pay for that service/feature, they even will not know that there is a paid feature which could be purchased on our web site. This is not my application, but the application which I'm developing for my client, and he thinks that our app could be considered as a "Reader app" (Review guidelines 3.1.3a), we don't force or ask the users to purchase anything. The iOS app is just a feature for the complex system developed on the web portal, so we just want to enable our web users to access their services in our mobile app. The app is completely functional without the paid features. Will we have to implement IAP, or not? Will we have a problem during the review process? What would u do if you were me?