Another article on phones that have already eliminated the jack:
This article makes sound quality one of the reasons to get rid of it. While it is true that the DAC in all phones and laptops are terrible, if they just replace it with a crap DAC in the lightening connector, the quality will still suck. You either need a great DAC like a Firefly which takes the digital file and sends through an awesome DAC making the 3.5 connection wonderful, or you go digital all the way and have great DSP in the headphone, something very few brands or factories know how to do.
DAC= Digital to Analog Converter
DSP= Digital Signal Processing