Jay Peters, writing for The Verge:

Apple bought music recognition app Shazam in 2018, and now it’s integrating it into iOS in another big way — a new Music Recognition feature can identify songs playing around you as well as in apps on your phone. And it even works when you’re listening to music on your headphones.

The new feature is available as a toggle in Control Center, but it does require a developer beta of iOS 14.2 if you want to try it right now.