Pen Cap Holes
The hole in the pen cap could make people think there is something wrong with the cap’s design. However, they actually installed the hole to let air flow in freely in case the cap is accidentally swallowed. Many people have the habit of putting pen caps in their mouths, so putting a hole in a pen cap makes sense.
iPhone Camera Hole
The tiny hole that is beside the iPhone camera lens is not a secret camera, so you do not have to worry. It is a microphone – one of three, actually. Since the iPhone 5 was introduced, Apple has added three mics to its smartphones to make sound recording easier no matter how the phone is held.