YMusic - YouTube music player & downloader v3.1.0 for Android - Download
Listen to music on YouTube even when your screen's turned off
But while this is YMusic's main feature, that's not all it does. From this app you can also download any song from YouTube and save it in different formats right to your device.
YMusic YouTube music player & downloader is a very interesting application. With it, you can easily stream music from Youtube as though you were using Spotify or a similar application. And as if that weren't enough, you can also use it to download videos to your device's memory and listen to them even without an Internet connection.