The extending the brand comment is exactly right. And it goes back way before iPhones too, Nokia is probably the best example. While people may not be able to h

The extending the brand comment is exactly right. And it goes back way before iPhones too, Nokia is probably the best example. While people may not be able to hum the melody of the original Nokia ringtone when asked spontaneously, I bet that they could at least recognise it when it is played. It's a catchy jingle that makes you think "oh that's a Nokia phone ringing".