The question is:
The Apple App store has a feature called Family Sharing. With this you are meant to be able to buy an app once and share it among a family. Will Family Sharing work with LuckGrib?
The short answer is: no. The most important sentence from the image above is that in-app purchases can’t be shared with family members.
LuckGrib uses the in-app purchase process to start the 14 day free trial as well as to purchase the product. As the Apple in-app technology is used for this process, and Apple does not support in-app purchases with Family Sharing, a LuckGrib purchase by one family member does not allow all other members to share the same purchase.
Note, there is a small exception to this is if you bought the app before it was offered using the in-app purchase process. Initially, you needed to pay for LuckGrib up front. There was no free trial - you had to pay for the app and then decided if it was suitable for your needs. As those early adopters have paid for the app itself (not the in-app purchases) they will be able to use family sharing.
In August of 2018, LuckGrib moved to the in-app purchase pricing model, which has been very successful.