http://www.techradar.com/news/essential-phone-will-get-a-headphone-jack-thanks-to-a-high-end-audio-accessory

Love it or leave it, the trend of removing the headphone jack is here to stay, and the new Essential Phone is no exception. 

That's not to say there's no way you'll ever get a 3.5mm port on your Essential PH-1. In fact, the company is actively developing an accessory that will instantly bring a headphone jack to your device.