It comes with a hidden curse, though: Families that share together can have all their devices wiped together and all track each other's locations, regardless of one's age. One could argue these are good things when you've chosen to opt into Family Sharing and location sharing. But, as your faithful writer keeps stressing, you have to know the risks in order to evaluate them.
Family planning
Family Sharing requires all the latest everything: iOS 8, OS X Yosemite, and iTunes 12. On a Windows system, you need to install iCloud for Windows 4. With all of that in place, Apple lets up to six people share media purchases across their own accounts. This includes apps (and in-app purchases), books, and anything bought via iTunes. A single credit card can (must, actually) be used to make purchases.
Chris Breen wrote a comprehensive guide to Family Sharing in September, after Yosemite shipped: "Get to know iOS 8: Family Sharing sets your iTunes purchases free." But what I want address is something reader Joey Archer alerted me to via Twitter: Family Sharing extends to Find My iPhone and Find My Mac, as well as Find My Friends.
This all makes perfect and lovely sense. When my children are old enough that I want to send them into the world on their own, I expect to outfit them with iPhones, and absolutely want to be able to know where they are if something happens or just to know they've gotten home safely without me having to have them check in.
But there's something a little interesting in how Family Sharing works. Even though you can denote specific accounts as belonging to 12-and-under humans, you can't prevent location sharing and other features from working across every device in a group, as opposed to just adults seeing everything, and kids not unless the adults allow it. Even if Apple offered this option for younger kids, teens graduate from account restrictions at age 13.
That sounds trivial, and I don't have teenagers yet, but it would seem to defeat the purpose of keeping tabs on your kids as appropriate while also not letting them know when you're, say, returning from an evening obligation, and give them time to kick their friends out and spray air freshener all over. (Yes, kids, we're on to the the air freshener.)
Adults could, of course, suppress their location by disabling Share My Location in Settings > iCloud, but then everyone in a group, including the other adult or adults, can't find them either. Let's not get coy about affairs and secret gambling habits and the like. It's a perfectly reasonable thing for an adult in a pair or other relationship to not want to be tracked by other people at all times, even when they trust them with their lives. And if your "family" is a group of people sharing a home and media, rather than a more conventionally structurally define one, it becomes even more of an itchy topic.
Without getting into games of logics and ethics, like the Prisoner's Dilemma or Two Hens and a Fox Cross the River, suffice it to say that the perfect panopticon of awareness of everyone's whereabouts in a group and the choice for someone to opt to be completely invisible aren't always the only desired options.
Wipe that smirk off your phone
The related issue is that Find My iPhone and Find My Mac become available to everyone in a family. Every device you possess and every device that anyone in your communal group has logged in to a participating iCloud account is part of this collection.
This is great when a device is lost or stolen. Rather than that person having to get to a browser or iOS device to log in and track their device, anyone else in the family can pull up the information. This is awfully handy while traveling together ("Ah, you left it in the hotel!"). If you disable location sharing, Find My iPhone continues to work for your account, and still provides limited access to the rest of your family group. Another family member can determine whether a device has an Internet connection, and can play a sound to help you or someone else find it.
Here's a potential downside: with location sharing enabled, every family member has the power to wipe every other device, iOS and Mac, that's part of the family group. Apple recognized that not all families are happy families, and that hardware might fall into the wrong hands. Thus, to erase a device belonging to another member of group, that member's Apple ID password is required.
So even in the hopefully unlikely event that one person has a device stolen or someone gains access to it and they have a password that can be guessed or is written down, that still only allows that malefactor to wipe the iOS and Mac devices belonging to that one account holder.
But this should alert you to the risk once again of writing down and sharing passwords. In a home with one or more shared computers, a sticky note on a monitor with the family's passwords--where it can be seen by family, guests, kids' friends, or even a burglar--becomes an even worse idea than it's been for decades.
The advantages of Family Sharing for the right set of people aligned in a group are fairly large. But Apple should consider offering more fine-grained controls than the coarse option of turning location on and off for the family group, offering better mapping to how families of all sorts actually work.
Glenn Fleishman is the editor and publisher of The Magazine, a regular contributor to Boing Boing and the Economist, and a senior contributor to Macworld.