They spent 30 minutes shopping and playing their music. So I walked over and offered them a pair of headphones to listen to their music. Turns out, they have an iPhone so there’s no headphone jack.

You've probably seen noise-cancelling headphones become pretty widespread ... frustrated that the noise of the plane drowned out the music playing through the electronic headsets on the flight.

So, how do these headphones keep outside noise out if they're not blocking the ... used to cancel the unwanted noise is also used to play music or podcasts, and it does both these jobs at the ...