Family Sharing, a feature due to debut with Mac OS X Yosemite, should bring a measure of sanity to households full of Apple devices. The idea behind Family Sharing is simple: You have multiple people in your home and just as many Macs, iPhones, iPads, and iPod touch units. And yet there’s no good way to share content purchased from Apple’s online stores—especially if they were purchased under different Apple IDs—or to coordinate family-focused information among those devices. Family Sharing was designed to address these issues.
For example, Dad’s got Casablanca on his Mac, Mom won’t stop grooving to her copy of American Idiot, teenaged Aisha has a lock on the entire Divergent series, and if you want to play Monument Valley, you have to negotiate the iPad away from Little Jack. Now imagine if all this media was purchased this way:
Each member of the family (up to six people are allowed) joins the Family Sharing group, which is—and this is the key, figuratively and literally—associated with a single credit card. Without sharing Apple IDs and passwords, any member of this group can download almost any media purchased by any other member of the group. Additionally, many future purchases can also be shared. (Apple indicates that not all media will be eligible for sharing.)

With Family Sharing you can spread your purchased media around with other family members.
This doesn’t mean that you have to give Little Jack carte blanche access to any music, movies, TV shows, audiobooks, ebooks, or apps he wants to lay his hands on. Parents will be able to switch on an “Ask to Buy” feature that requires those members designated as children to ask permission before making a purchase. When they do so, a notification appears on a parent’s device detailing who is making the request, what they’re attempting to purchase, and how much it costs. The parent can elect to decline the request or review it. Once reviewed, the parent can then approve it. And, yes, this means that you can now create an Apple ID for children under 13 years old.
Family Sharing goes beyond media sharing. It also allows families to share a family photo album. When you set up a Family Sharing identity, a family photo album is automatically created within the Photos app on the devices of all the members of the family. For example, when Aisha uses her iPad to grab a picture of the new kitten tearing into the drapes, that photo is synced to iCloud, where it will then sync with Dad’s iPhone. As with other shared photo streams, you can add comments to images.
Similarly, the family can share a calendar. Any events created on that calendar by one member of the family will appear within the Calendar app of all devices that belong to the Family Sharing group.

You can also keep tabs on where members of the group are.
Family members can also share their location with each other within the Find My Friends app. If you’d like to confirm that Mom is stuck in traffic, it’s easy to do by launching the app. (If a member would prefer to not be tracked, they simply make their location hidden.) Similarly, if your spouse, parent, or child has a habit of misplacing their iOS device, you can help them find it using the Find My iPhone app. Family members just turn on the sharing option on their device, and if the device is lost, another member can locate it and command it to play a sound.
Alas, Family Sharing doesn’t provide user accounts or profiles, a feature many a parent has been hoping for since at least the first iPad. Rather, Apple still seems content with assuming that “multiple users” means “one iOS device per person.” But even though Family Sharing won’t help us better share a particular device between multiple family members, at least we’ll no longer have to buy multiple copies of an app or tune—or all share a single “Purchasing Apple Stuff” account.