Interesting idea. As a subscription app (like Spotify) the membership or subscription model would be shifted in several ways resulting in a presumably very large aggregated audience. I assume there would be significant value to the data these "members" would agree to provide?

So, would the numbers work to benefit a single museum enough to get them to sign on? Would it be worthwhile for a cultural consumer to download the app and maintain it for, say $4.99 a month?