Tube Master is the best solution for your iPhone when listening to songs at Youtube in lock screen mode. It can also completely replace the YouTube application to reduce the capacity of the download. It weighs less than 10Mb and supports most of the features YouTube provides. How to use Tube Master is not difficult when it is designed with a simple interface, including YouTube video search tools. After downloading, find the songs you want to hear to, you can still turn off the screen without losing sound. This is a great advantage that the original YouTube application does not have, helping you enjoy excellent music listening moments.