Have you ever wondered what that HDR toggle in your iPhone's camera options is for? And why you want to use it? HDR stands for High Dynamic Range and refers to a scene that includes both bright and dark elements -- the sun, reflecting off water, with deep shadows in the tree lines, or even a regularly lit person standing against the glare of an open window. When we talk about HDR photography, we are referring to taking photographs of such scenes. Unfortunately, unlike the human eye, camera sensors need a little extra help to get that done. So, in this week's iPhoneography column, we're going to discuss more details about HDR and how best use your iPhone's camera to get the most dynamically awesome photos ever.