Google has launched the YouTube Go app. It works on 2G networks and it is best for 2G networks or slow networks. It is used for watching video not watching the channel. You can download It app from Google Play Store.
In This app, you can easily watch videos. When you click on a video, It will show you the preview of the video and it also shows you that in which quality you want to see that video it depends on you that on which quality was the video as basic quality standard quality and high quality then below the video quality you can see the play or download button so if you want to play you can click on play button but if you want to download the video you can click on the download button and in which quality you have selected the video will be downloaded .
YouTube Go is also can be used to share offline saved videos. The screenshots are below.