YouTube Background Audio in iOS 6.1

For some reason, the latest version of Apple's mobile operating system breaks one of my favorite features: playing videos in the background. It worked in Apple's old YouTube app, YouTube's mobile site and almost any other video app/site (an important exception is YouTube's official app). Close the app, double-tap the Home button, swipe from left to right and tap the "Play" button to continue playing the video in the background. In iOS 6.1, the "play" button doesn't work.

It's a great feature for music videos, podcasts, ambient sounds and it's unfortunate that Android doesn't include it and Apple (accidentally?) disabled it in iOS 6.1. Until Apple fixes the bug, you can install two third-party YouTube apps that use some undocumented APIs to support background audio: McTube and YouPlayer. McTube continues to play the video after closing the app, while YouPlayer lets you manually enable background audio.