What is the happy face on the lock screen and how do I access it?

when the screen lock comes up and the notification icons are at the bottom what is the happy face icon next to the email notification?

could it be mixradio icon? - added it to your home notifications options (quick actions)? settings/notifications+actions is where those are set. Screen shot would be helpful if you could post one :) but my guess is that one of your quick actions is set to mix radio?