Comment by komali2

Good analysis, and that doesn't even include the phone itself:

Having a 3.5mm Jack on a smartphone:

PRO:

- Compatible with nearly 100 years of audio technology

- Inclusion does not prevent usage of other means of wired/wireless audio transmission - usbc, bluetooth, wifi

CON

- Phone thickness minimum is hard-set to 3.5mm (not even sure this is a con)

- ....cost to.. design? I don't even know.