A pin pricked through the iPhone speaker increases volume?

Actually, yes it does. Quite a bit.

What you are doing is poking a hole though the plastic diaphragm that generates the sound by moving fast, so you are increasing the airflow around the diaphragm and making the sound louder. But: Enough pin pricks and you’ll cause noticeable sound quality reduction and a buzzing sound whenever bass-y sounds are played.

you best not be sticking needles in your $400 phone!

I always use the headphones if possible, since those have much better sound quality and volume. I agree with heyu.

Pin pricks work but you can do a lot better if you remove the tape entirely. You will double or treble the volume. I removed the tape covering the speaker holes on mine and I can finally hear everything in a noisy environment without needing to strain. I’ll probably get a lot more dust in there now, but the price is worth it for louder audio.

@tan, about a year and lots of dents and cracks after my previous post, and I too have gotten rid of the earpiece tape and padding over the bottom speakers, now that my warranty has gone buh-bye.

Oh-so-loud ringing goodness.