Recently I wanted to offer my customers the opportunity to donate some money. No extra features, just a clean donation option. In-app purchases seemed to be the best option. The idea is to have a list of products which have a price and contain “donate” in their product ID (Fig. 1). In the app the list of products can be retrieved and shown when a donate button is tapped. If donations have been given can be checked by enumerating the existing licenses and looking for the “donate” term (Fig. 2). Reasonably simple right? Well the principle is simple, but in-app purchases are a bit tricky to develop, debug and get through certification. (It took me 7 submissions to get it right..) Those are the things that can result in certification failure: no internet connection -> exception store does not respond properly -> exception error message looks to much like a…