Pro plan accross multiple devices

Hello, I‘m planning to buy Photon 2 Pro Plan on my main iPad Pro. But I would like my sister’s iPad to have access to the pro features too. She’s in the same iCloud family as I. Will it work ? Considering I have my icloud purchases shared within my family.

I don‘t think that it works, but I‘m not completely sure. In the app store, there is no label that shows „supports family sharing“ (is this the english name of this feature?). When I look for example at GoodNotes, there is this possibility listed.

You are right I think. That’s quite embarrassing though. Thanks for bringing this detail to me.