In-app purchases: Share user In-App purchases between Android and iOS

Question

I'm planning to add In-App purchases to my Productivity app. Enhanced features are purchase products (e.g., freemium). I would like to have user access to purchased feature on both Android and iOS, if he has purchased on any one platform. Technically I plan to store purchase information on server and have it retrieved whenever user logs-in on either device, and unlock the feature if already purchased.

Is this allowed in both iOS and Android?

Apple App Store Review Guidelines on Section 11 have this explained.
Points "11.1/11.2" and "11.14" sounds conflicting (or I'm missing something.).

On Android, I do not see this point mentioning in Policies.

If you had any experiences (w.r.t sharing purchase info between devices) that I should take care additionally, any suggestions are welcome.

Answer 1

I'd like to add a note about subscriptions. Here's the quote from Apple guide:

Cross-Platform Considerations

Product identifiers are associated with a single app. Apps that have both an iOS and macOS version have separate products with separate product identifiers on each platform. You could let users who have a subscription in an iOS app access the content from an macOS app (or vice versa), but implementing that functionality is your responsibility. You would need some system for identifying users and keeping track of what content they’ve subscribed to, similar to what you would implement for an app that uses non-renewable subscriptions

Link to Apple docs: https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/StoreKitGuide/Chapters/Subscriptions.html

Quote from Android docs:

You can also build on your existing external subscriber base from inside your Android apps

• If you sell subscriptions on a web site, for example, you can add your own business logic to your Android app to determine whether the user has already purchased a subscription elsewhere, then allow access to your content if so or offer a subscription purchase from Google Play if not.
• You can implement your own solution for sharing subscriptions across as many different apps or products as you want ...

Link to Android docs: https://developer.android.com/google/play/billing/billing_subscriptions.html

At the moment of writing this answer (May 23, 2017) Windows Store doesn't have subscriptions but they were announced during the latest BUILD conference. Some details here and here Subscriptions should be available later this summer.

Answer 2

Answering myself. I submitted to App Store mentioning this case and got it approved. I'm yet to submit to Google Play so not sure about it.

Below the snippet I mentioned in App Store review notes that may help some

If user already purchased premium outside the app(our website or Android app), then we are unlocking Premium as soon as user logs-in to the app on iOS device. We do not include any button or link or information inside this app regarding purchasing outside. If you have any concern or comments regarding this, please let us know.

Additionally mentioned that our in-app item's service is based on user data at our server and not solely on iOS platform. I think this is the key point that makes sense to reuse user's purchase of our service. However, I do not find this case mentioned clearly in App Store review Guidelines.

Answer 3

[Update for April 2019]

As I've already answer here - from developer Apple guidelines:

3.1.3(b) Multiplatform Services: Apps that operate across multiple platforms may allow users to access content, subscriptions, or features they have acquired elsewhere, including consumable items in multi-platform games, provided those items are also available as in-app purchases within the app. You must not directly or indirectly target iOS users to use a purchasing method other than in-app purchase, and your general communications about other purchasing methods must not discourage use of in-app purchase.

So like @siddharth-gupta explain in his answer:

Apple's rule basically states that if you have a digital product in your app (in your case, your subscription), the only way to pay for it should be via Apple's in-app purchases. If instead of using in-app purchases, you redirect the user to pay using any other method, your app risks getting rejected.

Note: this Apple statement for April 2019 -> and can always change. To avoid potential rejection/ban Always verify it with current official Apple Documentation