Apple's answer: Regarding guideline 3.1.3(d), while we understand that users can message real specialists, the conversation is not done in real time. Guideline 3.1.3(d) says that “real-time person-to-person services between two individuals (for example tutoring students, medical consultations, real estate tours, or fitness training)” are exempt of the in-app purchase requirement, however, unlocking the ability to message another person is still considered a digital service where in-app purchase is required. Asynchronous text-based person-to-person services (where a user leaves messages and receives replies back at a later time from a real person) are not considered real-time services, thus in-app purchases are required. To resolve this issue, it would be appropriate to revise your app and implement the in-app purchase API. They consider us getting money for allowing user to unblock chatting with expert and consider it as a digital service.