Free subscriptions are a way for developers to put free subscription content in Newsstand. Once a user signs up for a free subscription, it will be available on all devices associated with the user’s Apple ID. Note that free subscriptions do not expire and can only be offered in Newsstand-enabled apps.
Note: If you want to charge for your content you need to make sure you always have in-app purchases for that content approved by Apple before using them in the Publishing Center.
Creating an In-App Purchase for a Free Subscription:
1. Log into iTunes Connect.
2. Click Manage your Applications.
3. Locate your application and click on it.
4. Click Manage In-App Purchases.
5. Click Create New.
6. Select Type. Here you want to pick 'Free Subscription'.
7. Fill in the details:
Reference Name: This is the name used in the financial reports sent to you. This can be any name but we advise to make it unique, otherwise it can be difficult to distinguish in reports.
Product ID: We suggest you follow suit with your App Bundle Id, and make your product ID something like 'com.companyname.appname.freesubscription'. You will need to copy this across to the Publishing Center soon, and it is important that these ID's match exactly.
Cleared for sale: Always tick 'Yes' here.
Language: The language that your products name and description is in.
Name: The name of your issue (you can change this in future).
Description: The description of your issue (you can change this in future).
8. Scroll down and click NO for "Hosting Content with Apple".
9. Upload a screenshot for review processes. This image is only ever seen by Apple review team, not the general public. We suggest uploading your app's splash screen here.
10. Click Save.
You will now see your free subscription in the list of all your in-app purchases. The new products will have the status "Ready to Submit".
Once you have completed these steps for ALL in app purchases, select all of your new products using the check-boxes on the left and and click the Submit for Review button. Apple will now review these products before approving, which normally takes approximately 4 to 5 working days.
11. Once your free subscription is approved, log into the Publishing Center and go into your app. On the left hand side under iTunes Connect, click on Subscriptions. Here you will see a field under Subscription Settings called Free Sub Product ID. Enter your Product ID (e..g 'com.companyname.appname.freesubscription') here.
How do I find my iTunes Shared Secret?
You can find your iTunes Shared Screen in iTunes Connect. Log in, and go to Manage Your Apps. Then click on Manage In-App Purchases. Scroll down to the bottom of this page and you will see a link "View or generate a shared secret". Click this, and you will find it here or you can also set it up if you haven't already.