Satellite navigation systems use GPS coordinates to determine where you are and how to get to a destination. You simply type where you want to go and then let some clever software do the rest. Knowing where you are, or more importantly reporting where you are can be a big part of any job, GPS coordinates are exactly that.
Photos are a great way of communicating detail and capturing state. Mobile phone cameras have made taking photos convenient and cost effective, why carry a separate camera when the one on your phone is more than capable.