Shazam a song from Instagram
There was an unanswered question about this to which I could not reply so here's how to Shazam a song that is playing in a different app like Instagram. (This is on iOS15, not sure about older iOS)
Go to Control Center, scroll down to Music Recognition and add it. Now whenever you want to Shazam a song that is playing in an APP you just pull down to show (Wifi, Torch, Camera, etc) and there you have the Shazam logo. Press that and voila. In a few seconds you will see the song (hopefully).
iPhone 13 Pro, iOS 15