Apple confirmed today that Family Sharing now includes auto-renewable subscriptions and non-consumable in-app purchases (via MacRumors). A non-consumable in-app purchase is like a feature you can unlock in an app rather than coins or currency used for in-game items.
Developers must enable Family Sharing in their app before you can share your purchase with family members. Devs can also choose to implement Family Sharing or subscriptions and in-app purchases or choose to require each member of a family to purchase their own subscription or in-app items.
To enable sharing of new subscriptions and in-app purchases, launch the App Store, tap your avatar in the upper right corner of the screen, and then tap on "Subscriptions".
Lots of apps offer premium subscriptions for things like ad-free use or unlocking special new features that can really make an app more useful. And so it's good to see Apple extending its Family Sharing feature to include subscriptions and non-consumable in-app purchases, allowing you share these unlockable features with your family members so they don't have to buy them, too. And now that sharing is enabled, it could make some people more willing to buy these subscriptions and in-app purchases than they would have been previously.