In June, at the (virtual) Worldwide Developer Conference, Apple announced that developers would be able to offer Family Sharing for their in-app purchases and subscriptions. Now you can.
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Previously, Family Sharing allowed you to share purchases you’ve made using your Apple ID through iCloud Family Sharing, which includes apps, music, movies, and an Apple Music subscription. Now in-app purchase sharing is available with macOS Big Sur, iOS 14.2, and iPadOS 14.2.
There’s a new toggle is available in Settings > Apple ID > Subscriptions to let users share eligible subscriptions with family members through iCloud Family Sharing. You will also find another new option to disable subscription sharing for a specific app.