In today's episode number 'who's still counting' of the Galaxy S8 rumor saga, it is suggested that a rear-mounted fingerprint sensor will make it to the next-gen Samsung flagship. The reason cited is that in initial testing of the fingerprint sensor embedded in the display has proven inaccurate, and a dedicated sensor is still needed. Why, what's wrong with the Home button, you ask? There will be no Home 'button', strictly speaking, as multiple sources have already stated, and the entire front of the phone will be mostly display. That's why when Synaptics (a Samsung component supplier)...
Source: http://www.gsmarena.com/samsung_galaxy_s8_to_come_with_a_rearmounted_fingerprint_sensor-news-22216.php
