YouTube for iOS finally gets iMessage support in the latest update
As the title says, YouTube for iOS finally supports iMessage, so users will now be able to share videos faster and easier than ever before. It also means that all videos that you receive in the Messages chat can be viewed within the app, so there's no need to exit and open up another app to watch it.
Sharing videos in the Messages app is very easy, so tap the Share button and choose the corresponding option to send the YouTube link in Messages.
Also, Google another gesture that will allow YouTube users on iOS devices to remove videos from playlists they have created by swiping left or right.
These are all the changes included in the latest update, so make sure to update to YouTube version 12.38 in order to benefit from what they have to offer in terms of functionality.
source: App Store