You probably already know you can talk to your phone. You may think this is a little bit of a gimmick, but it is a powerful feature that can the extremely helpful in certain situations. The place I use it most often is in the car. There is a cradle that holds my phone, and I tell my phone to send someone a message, or call someone. I even have been known to dictate emails.
Perhaps you don't know what you can do with your voice. So here is a link that gives you some great tips: howtogeek.com/use-your-voice