The rear camera has to be on for it to work. If you have the front camera on it'll grey out.
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The people of XDA, including the Devs. Do not have to help you. We all choose to help. Everyone also starts somewhere.
City I live in makes and invented the Kitkat... I run Kitkat on my device. Aww how cute.
CM11 N9005(Note 3) - Nexus 5(D821)