Small Black Hole Between Your iPhone Camera And Flash, WHY??

No matter how much we call ourselves a pro in using and understanding iPhone, there are many things we still don’t know about it. Today I came up with something we notice every day in our iPhone, but we are still unable to figure it out.

Have you ever wondered why do we have a small black hole at the back of our iPhone between camera and flash? Do you think is it a reset button or something?
Let’s find out. Also, watch the full descriptive video in the end.