We knew it was coming eventually, but just before the Google I/O keynote began, Google updated its developer documentation with more details about Family Library. Most important, we have a launch date of sorts: July 2nd. That date marks when app purchases will be shared in the Family Library by default unless the developer opts out.

For those who aren't familiar, Family Library will be a way for trusted family members to share Play Store purchases among one another. We have seen bits and pieces popping up in our APK teardowns for a while now. When it comes to video purchases, for instance, we can tell that you will be restricted to streaming the same title on only one device at a time. Moreover, it appears there will be a restriction on the total streams coming from the same library across multiple devices.

Importantly, developers can decide whether or not purchases prior to July 2nd can be shared among families. Unlike purchases after July 2nd, developers must opt in for older purchases to go into the library. Here's the full text from the support site:

When Family Library becomes available to users, up to six family members will be able to share purchased apps on Google Play.

Opt-in previous purchases to Family Library

By default, all paid apps purchased after July 2, 2016 (when the Developer Distribution Agreement update takes effect) will be eligible for Family Library.

To provide a seamless user experience, we suggest you allow users to share purchases made prior to this date as well.

To opt-in previous purchases:

  1. Sign in to your Google Play Developer Console.
  2. Select an app.
  3. Select Pricing & Distribution.
  4. In the "Family Library" section, select the checkbox.

Users will see whether previous purchases of your app are eligible for Family Library on your store listing page.

App requirements & eligibility

  • Once you've made previous purchases available for Family Library and submitted your app update in the Developer Console, you can't opt-out—your selection is permanent.
  • Your app doesn't need to be part of Designed for Families to be included in Family Library.

We will surely hear more about this as I/O proceeds, so stay tuned.