We've all had the harrowing experience of locking our phones or quickly checking a Facebook message or notification to suddenly hear dramatic silence coming (or not) from our headphones. This is because we were listening to a YouTube video, which for iPhones does not currently support out of app use.
However with a simple trick and a pair of headphones with a control pad (the little white volume up and down/play button) you can get the sound from the YouTube video open in the app to play. Simple exit the app or lock your phone and press the play button on your headphones.
This causes the sound of the video to play through the earphones and you become free to listen to endless music without apps such as Soundcloud and Spotify which often charge money for the same lossless services.
As a warning, the auto play feature does not operate, so once a video ends so does the sound and you will have to repeat the trick.But this is a cool hidden, or maybe accidental feature which may solve some of your musical consumptions desires.