In app purchase - method to allow full control of adding products from personal server = allowed?

Question

I have a very strait forward question (and yes I've looked though apple documentation to see if this has an answer but no luck... I may have accidentally missed it though)

Here's my plan:

The problem I've been trying to find a workaround for is that if the admin would ever want to add a product, he would have to log into iTunes connect to add it and also add it in a custom control panel. We, obviously, don't want to make him suffer that so I've been looking for a solution but I need you guys to tell me if it's allowed by apple. Basically I will take over most of the product handling on our servers and will only go to apple with the transactions. This means that apple will not have an in-app purchase set up for ALL the products... only one for each length of subscription (1 month, 3 month... etc) and a few consumable in-app purchases for the various prices of the issues/singles

Side note: I will be selling monthly issues that contain multiple singles for each day of the month. The user will be able to download a full month or a single day at a time if they like.

DEFINITION OF CONSUMABLE PURCHASE - products must be purchased each time the user needs that item. For example, one-time services are commonly implemented as consumable products.

So I will store all the information in our server about the products and if someone chooses to buy a single month's issue that was set to 4.99 (on our server, not apples) then the app will run the in-app purchase with apple that is listed for the 4.99 tier. Whenever a person opens the app for the first time, their app will send some information to our server and they will have a row set aside for them where all the information about their purchases will be recorded so that they can restore them if they switch over to another device.

If you guys think i'm safe in doing this, please let me know so that I can proceed. Also, if this method helps anyone, feel free to use it!

Thanks, Matt

Answer 1

I think your restore process might be flawed. You talk about the app sending some information up to your server, but what is that information? There is no reliable way to uniquely identify a user across different devices.

If you want to continue on this path you'll want to make sure that your recovery and failover process is very solid. Try out every imaginable scenario. From an app store submission point of view, you'll want to consider a token/coin-based approach. Of course, Apple's guidelines are fairly loose and subject to change so it's always possible you'll get rejected, but tokens are certainly more solid than simply using the same generic in-app purchase.

In a token system, you would set up in-app purchases for different numbers of tokens that the user can purchase as a sort-of virtual currency only valid within your application. Then users can spend these tokens on any items that you dynamically create.

Server-side this means you'll need some way to store how many tokens a user currently has and a way to uniquely identify a user across devices, which is a fairly uncertain proposition. Instead of storing the number of tokens each user has, you could implement some sort of hashing algorithm that generates a hash from an in-app purchase receipt and then sends it up to your server. If the app crashes or the network dies after purchase but before sending your hashes up, next time they open the app you can recalculate all of the hashes, send 'em up, and if the server doesn't recognize a hash it just adds it to the database. Then if a user wants to restore their purchases you simply recalculate the hashes on the device using the in-app purchase receipts you'll receive and then send them up to your server and ask the server to figure out for each of those hashes, how many tokens the user has left. You could think of it like a gift card system, where each hash is one gift card.

Again, app store rules change and if apple thinks you're trying to game the system and not provide a useful experience they have the right to reject you. It could be worthwhile to open a Developer Technical Support request and see if an apple engineer can provide you with a better solution or tell you if the reviewers are likely to accept your application.