Right??, what IS that little dot next to your camera on your iPhone? It's so small, it's easy to miss let alone realize it's even there! It actually does serve a purpose...it's another microphone, one of three on the device! Another microphone is hidden under the speaker grill in front and another one is at the phone's bottom edge.
This microphone also helps with voice recognition when you're telling Siri what to do.
Photo courtesy, Michelle Taylor's iPhone