One of the things many people wanted not to believe when the barrage of S8 leaks came around over the past few weeks was the new position of the fingerprint sensor. Not that it would be on the back of the S8 duo per se, but its location next to the camera lens. Like, really close to it. And off-center. Perhaps not wanting its new flagships to look similar to many other Android handsets that have a circular fingerprint scanner centered horizontally on the back, Samsung went with an oddity that's bound to create some problems for those that use both that sensor and the main camera a lot. And...
Source: http://www.gsmarena.com/samsung_knows_how_bad_the_position_of_the_fingerprint_scanner_is_on_the_s8_and_s8-news-24269.php