I haven’t seen any. I am hoping that some of the apps for home automation enable this. It seems crazy to have to pay multiple times to enable premium features for an app that controls lights in your home.
You can share content that you purchase from Apple including music, movies, TV shows, apps, and books. You can also share your Apple subscriptions including Apple One.
I read a couple things about that change on other sites but couldn't find anything from Apple about it, even on developer.apple.com. Looks like it's up to the developer to decide if they want the IAP to be family-shareable. Maybe someone who is a developer could chime in.
The description of the Komoot app says that in-app purchases could be possibly shareable (whatever that means) but it didn't work and according to a chat with support in-app purchases are not shareable yet.
🤦♂️