In addition to the test build, there is an official update to the Android powered YouTube app that was released on Wednesday. This update allows you to find videos, playlists and channels together in search results, and there are now tabs on channel pages for activity, videos and playlists. The proverbial bug fixes are included with the update, including one that removes the Cast icon that appears over the app when Bluetooth is connected.
After we updated the app on our HTC DROID DNA, there was no change to the icon, which could mean that the dog-gone bone icon is being sent out to random YouTubers when they update their Android app. You can let us know if you received the test build of YouTube by dropping us a comment in the box below.
source: YouTube via AndroidAuthority