If you enable HDR photography by tapping the HDR icon in the Camera app, your iPhone will save two copies of the image in your photo library i.e it will save the ‘default’ image (without HDR) along with the one with HDR. This will fill up the storage of your iphone, as HDR photos are larger in size than the normal ones. So, If your iPhone’s storage is low, or you prefer to plan ahead, read ahead to save a significant amounts of storage space on your device.
Step 1: Launch Settings on your iOS device and tap Camera.
Step 2: Flip the Keep Normal Photo switch to the OFF position.
Since the iPhone5s, HDR is available with both the front-facing and rear-facing cameras. You also have the HDR Auto option to let your iPhone camera use HDR when it’s most effective.