Cameron Diaz: 'The Body Book' Available Now!

Cameron Diaz carries a brass knuckle style iPhone cover while heading to her car on Monday (December 30) in West Hollywood, Calif.

A few weeks ago, the 41-year-old actress was spotted singing for a scene in her upcoming film Annie in New York City.

PHOTOS: Check out the latest pics of Cameron Diaz

“One of my proudest moments! Receiving the first bound copy of The Body Book!! @thebodybook LADIES!! I wrote this book for YOU and YOUR BODY.. And I’m so excited to share it with you!! You can pre-order it now,” Cameron recently wrote on Instagram with a pic. Check out the pic below!

In case you didn’t know, The Body Book: The Law of Hunger, the Science of Strength, and Other Ways to Love Your Amazing Body is available on Tuesday (December 31).