If you use the YouTube iOS app to listen to songs, you might find it annoying that after you lock your device, YouTube stops playing audio. Here’s a simple trick to let the YouTube app continue playing audio after you’ve turned off your iPhone or iPad’s screen.
When on a video page, tap on the share button (the one next to the “+” button) located at the bottom, and then tap “Message.” Once the message compose screen appears, you can lock your device, and still have the audio continue playing in the background.
The perfect solution would let you play audio even after closing the app, but this is still pretty good if you’re a regular user of the YouTube iOS app. YouTube prohibits playing just audio via its API, so it’s unlikely we see an audio-only YouTube app on the App Store, but we do hope tweaks like ProTube and YourTube are updated for iOS 7, once a jailbreak is available.[via Reddit]