title: In App Purchase: dynamically add non consumable items
body: <p>I'm developing an app where the user can purchase digital maps, charts and so on. I'd like to wrap these in in-app-purchases. The thing is that I don't know beforehand how many charts there will be, as I'm getting them from another source from the net. There could be hundreds.</p>
  
  <p>I have a server that periodically gets the charts from that source and stores them locally; there may appear new charts in the future or disappear existing ones. All this without manual intervention. </p>
  
  <p>There are three distinct types of charts. </p>
  
  <p>My first solution was to create three consumable items and let the user buy these; this was working fine but unfortunately Apple rejected it, since they require charts to be "non consumable".</p>
  
  <p>But I'm quite at a loss how to implement what I want with the non-consumable type. If I create these three types as non-consumable, and the user buys one, he will get all the other charts in that group for free, since a non-consumable item can only be bought once.</p>
  
  <p>The only solution I can think of is to create a non-consumable item for every single chart. But that's something I want to avoid at all costs: as it is now, the charts are periodically fetched from the remote source without any manual work on my side. I'd like to keep it that way. I don't want to manually create a new non consumable purchases every time a new chart appears.</p>
  
  <p>Any ideas how to make this scalable?</p>