OnePlus has officially confirmed a couple of things about the upcoming OnePlus 6T - that it will have an in-display fingerprint reader and that it will lack a 3.5mm headphone jack. It turns out these two are connected. In a lengthy interview co-founder and CEO Pete Lau says that removing the 3.5mm jack was necessary in order to free up room for the in-display FP reader (which the company calls Screen Unlock). This echoes Apple's justification of removing the jack to make room for the Taptic Engine. Apple lead the way to jack-less phones, but Android makers were eager to follow...
Source: https://www.gsmarena.com/oneplus_ceo_talks_about_how_the_indisplay_fp_reader_led_to_the_removal_of_the_jack-news-33559.php
