I am actually going to have server support but I need working receipts for the verification, i.e. not xcode generated but sandbox and later production. Now, as I am trying to do sandbox testing, Apple doesn't provide any information about how to setup products for IAP in the sandbox environment, so I assume you have to create one in App Store Connect. When trying to define products in App Store Connect. Apple says the following: "After you create an in-app purchase or auto-renewable subscription product in App Store Connect, you submit it to Apple for review. If you are submitting your first in-app purchase, you must submit it with a new version of your app." How am I supposed to implement and test IAP if I need to submit the app version before it's done? This just seems weird and my assumption of creating IAP products in App Store Connect seems faulty. I just can't find any useful information in the docs of how to actually do the sandbox testing. You say there are three ways of testing, I guess they are listed here. This link as most others only refer to "Create a sandbox tester account", no information about whether sandbox requires some other way of defining IAP products or what steps are necessary to make sandbox environment work.