All IAP services like Google, Apple and Amazon basically encapsulate the actual subscription functionality, including order process, billing, payment and others. The billwerk system integrates more or less as a monitor and data collector of these services. The control completely resides within the IAP services. However, especially when offering a product in several of these ecosystems and most probably even separately, the billwerk system is the tool to gather all information at a centralized point. With this approach product KPIs can be analyzed and reported as a whole.
To satisfy the growing demand for an IAP integration we decided to offer it as a separate product with its own pricing. Our Support will gladly answer your questions.