YouTube beta is aimed at those who wish to test experimental features that might or might not make it to the final version of the YouTube app.
YouTube has rolled out an official Play Store beta program for its Android app. You can join to help improve the program. YouTube beta program is open to everyone, app developers but you are not allow to share the feature you are testing until when its publicly launched.
How to Join YouTube beta Program
>>Visit the beta testing page here
>>Choose become a tester
>>Follow the onscreen instruction and you are good to go as a tester.
In other news, YouTube Go (lighter offline friendly version of YouTube launched in 2017) has crossed 100million download.