Google will enable a new family sharing system in Google Play later this year

Google's support page makes it clear that all purchases made after July 2 will be available for sharing with the Family Library system. Apps and content bought before this date will have to be allowed by its developer. Google didn't give away a launch date for the future, but "later in the year" seems like a surefire bet considering how the rest of the announcements were scheduled.
In the meantime, sharing a single Google account with your family members still remains a cumbersome, but functional option for not buying the same stuff multiple times.
source: Google via Android Authority
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