Youtube downloading is not supported anymore.
You can download videos and music from VK using an android app ‘Videoder’. Videoder is an android app that lets you download videos and music from VK, Youtube, facebook, instagram, voot and many other sites.
Open VK website and search for the video that you want to download and open the open you want to download
When you tap on a video a red download bubble appears on the left bottom corner of your screen. Tap on it to get the download links and choose the video or audio quality in which you want to download.
You can then choose the resolution in which you want to download the videos and start your downloads
Once resolution is selected a dialog appears which allos you to select your download location and start your download
You can tap on the download icon on the top of the screen to view your downloads. Or your can check them in notification panel