Many people still don’t know what this small hole is for

The purpose of the small round hole at the bottom of the phone:

The small circular hole on the bottom of your phone is actually a secondary microphone and plays a crucial role in the dual-microphone system, which contributes to noise reduction. This is a noise-canceling microphone built into most modern smartphones. Thanks to this microphone, your calls will be clearer and of higher quality. Without it, your voice wouldn’t be transmitted clearly to the listener.

Even in noisy environments, you can still hear and transmit your voice clearly thanks to this small hole. Placing the microphone on the bottom of the phone near your mouth allows for better voice capture and transmission, improving call quality.