1.When on your home screen* or in Google Now, just say ?Ok Google? to launch voice search, send a text, get directions or even play a song.
(Although I can't seem to get this feature to work from my homescreen?)
2.While listening to music on your device, you?ll see a full-screen album art when your device is locked. You can play, pause, or seek to a specific moment.
3. Emoticons available on Google Keyboard, and you can place them anywhere.
4. Jump to a specific part of a song or video from your lock screen. Just long press on the play or pause button and then select the point you want.