You’re walking round a physical store, and want to identify the song that’s playing. Turn on your iPhone, and it’ll identify the music and let you buy it from the iTunes Store, while paying a commission to whatever store you heard it in. Science fiction? No, it’s the gist of a patent application from Apple that involves location-based advertising on iPhone and other Apple wireless devices, allowing consumers to buy content. Of course, you can already do this using the iPhone’s Shazam application, which ties into iTunes, but Apple seems to have grander ambitions for such a technology. Whether it ever turns into a commercial service is another question.