Same happened with me once. And till date couldnt find out the association and what wrong we did or the association who they say we are associated with!
The trailer contains footage of the music videos produced (the part with the fancy effects and transitions synchronized with the music). It's basically a real-time video that plays within the app alongside your music - it doesn't output videos as files. I need to probably make that part clearer somehow.
I think the main reason is that the visualizations are driven by audio analysis, which is often inferior to actual videos edited by hand. This isn't designed to compete with videos made by people, only to provide a good-enough substitute.
I could implement a video editor to let people have more control over the visualizations, but people can already use existing video editors to do that instead if they really wanted to. So I decided that it wasn't worth the effort.
If you explore Apple apps for utilities/tools like Qr code reader, currency converter, call recorder, vpn, etc. you can find hell lot of similar scammer who are playing it hard for apple to catch.
