问题
I have implemented In App purchase in my existing application.
This application is currently available on app store as paid application, I want to update this paid application to free application with this In App purchase feature, where users can download it freely and have to pay for few features to unlock them.
But the problem is that, if I update the existing paid application as free application (with few features locked and user has to buy it to unlock it), what about the users who have already purchased this application.
Because when they will update to new free application, few features will be locked and they have to pay again to unlock them (why should they pay, if they have already purchased whole application previously).
回答1:
How about releasing a new paid version which writes some data to the application's data store recording the fact that is the paid edition. Then release a new version of the same app that is free but obviously does not record that. However, the free version looks for the data written by the paid version and unlocks the premium features if that record is found.
The only downside is that you'll be depending all paid users upgrading to the new paid version before you release the free one.
回答2:
Is there a way to check the version they are upgrading from?
If so, you could make the fully unlocked app version 2.5, and the locked free app version 2.2 and, assuming your current customers are on version 1.9, you simply check for this. If they are on version 1.9, they get "upgraded" to version 2.5.
回答3:
If the switch from paid to free is quite far away from the paid app launch date, it should be more acceptable. What I suggest is to enhance your free version with a new feature\content to satisfy those who had already downloaded and paid for it.
来源：https://stackoverflow.com/questions/2219868/what-about-the-customers-who-have-already-purchased-a-paid-application-when-upgr