Google have updated the YouTube app for Android. The updated app has improved search so you can find videos, playlists and channels together in the search results and there are tabs on channel pages for activity, videos and playlists.
There are also the usual bug fixes including fixing the Cast icon appearing over the videos when your connected to a Bluetooth device.
You can find the app in the Google Play Store.
* Find videos, playlists and channels together in search results
* Tabs on channel pages, for activity, videos and playlists
* Various bug fixes and improvements, notably a fix for the Cast icon appearing over the player when Bluetooth is connected