I have been using this TubeMate app about more than a year now. In my point of view it is the best alternative for youtube. I mainly used TubeMate for downloading youtube videos. We cannot download YouTube videos directly from YouTube, if need to download any one of the videos you should go to any site and search for it. It is not a satisfactory procedure but by using TubeMate you can simply watch YouTube videos and if you need to download them then directly download to the device. There is an option for download. We can download the videos is different quality. If you want full hd or if you want 144p there is option for it. We can also download the video in to audio. The other thing is we can also browse through any sites and we can also download anything. It can also be used as a downlader.
Although it is the best app for youtube downloading there is major problem for this app that is if you want to download high quality videos or download audio you need another app with TubeMate that is mp3 converter. Without this app we can’t download hd videos or audio. This is the major bug for this app.
But overall it is the best alternative to YouTube