I want to make an app where every single item is unique. I could not find out much information about the Store Kit in iPhone OS 3.0. Do I have to upload all these download-items to the App Store? Or can the download be made from my own server?
Example: I have 10 items in my app that people can buy. They are highly exclusive, so the one who buys item X, will be the only one who's got that item. after the purchase it's not available anymore.
Do you think it is possible to do that?
I would suggest re-asking this question on the apple developer forums - the 3.0 API is under an NDA and cannot be discussed on a public forum like this.
That said, I would imagine the in-app purchases are held to the same standards as app purchases - each item that you offer for sale must be approved by Apple.
My gut feeling is that the store kit is used to handle the transactions/purchases but you'll have to host your downloads on your own server. OR I suppose another method is to include all files in the app to start with (or in app updates), and that buying stuff merely unlocks that data. I think Burnout Paradise for the 360 does this. That's probably how someone can buy a car to use in game that someone else can see in multiplayer even if they haven't bought it.
I imagine I'll probably create a google app engine site and host my downloads there. That way the game can be more flexible. DLC content wouldn't be dependent on app update approvals.
I'd like to the have the option to host the files in the app store. That would be convenient. :)