Is there any Quiz/Forms/Survey type of app using Nostr?

I feel like that could be a killer app and easy to implement.

I envision this:

Nostr based form/survey/quiz app that creates a new Npriv+Npub that creates the quiz/survey. This is published as an event or series of events of some sort.

Then, users get two options:

1) use their own Npub if they wanna be identified with their answers 

2) use the Quiz’s Npriv to answer, this all users share the same Priv key and can’t be identified

The question would be on how to make the answers private in case that is necessary. Perhaps encrypting all “answers” with the original Npub so that only the creator of the survey (and owner of the Npriv) can see it?

This does, however, fly in the face of point 2). But hey, nostriches are smart, perhaps the trade off is: private + “KYCd” vs public + anonymous.

I know nostr:npub1gzuushllat7pet0ccv9yuhygvc8ldeyhrgxuwg744dn5khnpk3gs3ea5ds showed me a texting app that uses the concept in point 2) to create a private and perfectly anonymous groupchat amongst peers.

What do you think? Does it exist yet? nostr:npub1sn0q3zptdcm8qh8ktyhwtrnr9htwpykav8qnryhusr9mcr9ustxqe4tr2x nostr:npub18ams6ewn5aj2n3wt2qawzglx9mr4nzksxhvrdc4gzrecw7n5tvjqctp424 nostr:npub1dergggklka99wwrs92yz8wdjs952h2ux2ha2ed598ngwu9w7a6fsh9xzpc nostr:npub1l2vyh47mk2p0qlsku7hg0vn29faehy9hy34ygaclpn66ukqp3afqutajft nostr:npub1gzuushllat7pet0ccv9yuhygvc8ldeyhrgxuwg744dn5khnpk3gs3ea5ds