Ok, i don’t know how call it but here i’ll try to explain it…
I am developing an app and i am almost finished with it, and what i wanted to do is, first upload it as a free app for preview where the user has limited usage of it (like some features are blocked), it has ads that says to buy the full version and when the user bought the full version, it will automatically updates and unlock the other features.
The first thing that comes to my mind is to have 2 different apps the one for free and the other one is the full version and both upload it on the app store, but i saw some application that automatically updates their version after buying the full version.
How will i able to that?
Three words: In. App. Purchases.
StoreKit Framework Reference: http://developer.apple.com/library/mac/documentation/StoreKit/Reference/StoreKit_Collection/_index.html
Full Tutorial: http://troybrant.net/blog/2010/01/in-app-purchases-a-full-walkthrough/
Have fun