How can I limit ios app purchasers to one account?

Question

I want to create a social networking ios app which costs money, and when the user buys it they are allowed to create only one account on the app. So the purchase is associated with the account somehow... or the app has a specific id on each device its bought on... would I need to use gamecenter somehow...

How would I approach something like this?

Any help would be greatly appreciated.

Answer 1

First of all, more than one person may use the device (think a family with an iPad) so what your doing is inherently a bad idea.

That said, you can use an in-app purchase to let them buy account access - check with the server first to make sure a desired username is available, then let them use an in-app purchase to buy access, and on your server tie that purchase ID to the user name. Even if they deleted the app and tried to re-purchase (while logged into the same iTunes store account) it would see a purchase had been made and essentially be the same user. It even does kind of work with multiple users as they could switch iTunes accounts (though that is a pain).

I would also suggest trying to tie it to the users iCloud account in some way, which is easier for users to switch between on an device (a family might use one iTunes account but have separate iCloud accounts).

If you don't want to give Apple 30% of the registration fee, your only option is to have users sign up on the web and pay there, then have a login they can use in your app. Then it's a matter of trying to prevent duplicate logins on you server, although as a last point of thought, I can't remember a business that succeeded by refusing people's money.

Answer 2

Since you are creating your own account management system, just save the user information once they do the account creation bit and never show the option again. Because developers no longer have access to the device id, you may have problems identifying an existing user if they delete and re-install the app, but I am not sure that there is a solution to that problem.

Edit: As a commenter to this question mentioned, you can save things to the keychain. Check out this link for a good lib for modifying the keychain .

Answer 3

您可以在电话上生成唯一的ID，将其存储在钥匙串中，然后使用该ID与服务器进行通信。