the ISO settings control how sensitive the camera is to light. The lower the ISO setting is the less sensitive to light the camera will be.
If you are using the flash set your ISO to 100. Or turn off the flash.
If you are holding the phones with the Power button on your left, then the flash options button will be in the upper right hand corner of the screen.
Tap it for 3 different settings a lightning bolt looking icon with an "A" for "Auto", then a lightning bolt looking icon alone for "Always flash", tap again and the bolt will have a null symbol for no flash at all.
The ISO thing is on all cameras that have any sort of manual controls. Its a holdover from film cameras. You bought a roll of film that was for a certain ISO speed and color of light, which digital cameras do with the "white balance"
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