no, you go to an app store because you need a need satisfied

sure, you can create an app store leveraging NIP-89 to see what tools are available, an example is Coracle's Apps Tab or https://nostrapp.link

But, more importantly, most of the time, the discovery of the app that handles the need you want satisfied is matched in time by the moment you discover the need.

The example I was going on with Zapstr is that you might not be aware that you can listen to music or podcasts natively within Nostr. You were not even aware that was a thing. Or replace "listen to music" with ANYTHING else.

The point here is that the moment you run into this new use case you immediately become aware of the app that is able to provide you with the tool to serve that need.

Instead of you going to an app store to search for "nostr music app" the nostr music app comes to you at the click of an event.

And that is the case for every internet/nostr use-case.