YouTube Music will improve your singing sessions, as it is now widely rolling out the live lyrics feature on its Android and iOS apps. With this new change, the existing Lyrics tab gets a redesign, and now you will see larger text with better spacing to read out the lyrics. The YouTube Music live lyrics will show the current line highlighted in white, while everything else will be colored in a toned-down grey.
You will see a blurred version of the album art in the background of the live lyrics. YouTube Music uses a note to highlight audio before the music starts. While the YouTube Music live lyrics feature is rolling out, not all songs supported the feature earlier. However, with time, the support is gradually expanding. For unsupported songs, you still get the static lyrics version.
Multiple users (via 9to5Google) have confirmed that the YouTube Music live lyrics feature is rolling out for the Android app (v6.15) and iOS app (v6.16). You may want to force-stop the app and try multiple songs to get the live lyrics feature to work smoothly. Do note that this new change isn't bringing the Now Playing UI that adds comments, which is also currently under testing.
This is a nice touch to the YouTube Music app by Google, as this makes the app perform similarly to its competitors, such as Spotify. Apple Music and Spotify have supported the live lyrics feature within their apps for a long time now.