Third-party apps have to opt in to make the feature work, and many have already done so.
This is a big deal, and can potentially save you a ton of money.
But what about the developers?

Apple
Arent they going to be out of pocket?
James Abeler, founder and director of Firecore, which makes the excellentvideo-playing app, Infuse, thinks not.
Kudos to Apple for finally making it happen."
What Is Family Sharing?
Family Sharing works like this.
One person, lets say you, is the family organizer.
Sometimes you have to pick the family plan option.
Apple Music, for example, is $9.99 for an individual, but $14.99 for families.
Other services, like extra iCloud Storage, can just be shared.
If you previously paid for multiple subscriptions of the same app, now you won’t have to.
Abelers app, Infuse, is a great example.
Its so good that you might pay the $10-per-year sub for each family member.
And yet, Infuse is one of the first apps to offer shared subs.
To understand this, think about how you, yourself, feel about multiple subscriptions.
Do you have any?
And if so, do you have any you dont resent?
This is especially annoying in recent years, as developers have moved to subscription models for their apps.
And subscriptions are important to developers, because they bring in ongoing revenue.
That leads to developers abandoning their apps when revenue dries up.
So, these new shared subs are good for developers, and for users.