At this time, Apple and Google don't support family sharing for in-app purchased products, which means we currently do not have family sharing plans available for Drops.
Family sharing allows family members to share eligible content. In-app purchases, such as unlocking the features of a free app like Drops, is considered “extra content”, and thus, unfortunately, is not suitable for family sharing according to Apple and Google policies.
You can find more information about this from Apple here:
And from Google here:
We are constantly hard at work improving Drops, and this includes working on a solution to scenarios like family sharing. We’re currently investigating family sharing options, but do not yet have an estimate as to when this feature will be available. Please stay tuned!