To view Youtube videos in 360° degree 3D rotation angle (New feature).

Youtube has been introduced video broadcasting service in 360° degree 3D rotation angle. Visitors will be a new experience while watching video in 360° degree 3D rotation angle. 360 ° degree supported videos can be viewed via the Google Chrome browser. Through Android-powered devices, you can also enjoy this new video format. To view on Android you will need to
update your Youtube app from here or Playstore.

To create 360 videos you can use Giroptic 360cam , IC Real Tech Allie , Kodak SP360 , Ricoh Theta cameras those are compatible with Youtube. In order to upload a 360 degree video file, you'll need to modify the file with a Python script then convert to Metadata before uploading. 
To know how to create script for your file properly read the google support page here.