Youtube go is a mobile app and it is developed by google.
It comes now in beta version and it is on playstore
This app is mainly developed for who has less internet connection like 2G or less data and poor signal.It works perfectly in any problem in signal or data.
I am using when this lanuch in india.
You can download it from playstore.
This app many feature yet not come like design and sliding , like and dislike these feature will come soon.
Youtube go takes less amount of data to play video