Samsung devices do this by checking the orientation of your face through the camera. They will also stay unlocked by checking if you're still looking (while rea

Samsung devices do this by checking the orientation of your face through the camera. They will also stay unlocked by checking if you're still looking (while reading a long page of text, for example) and also pause/play videos when you look away. The problem, of course, is that none of this works when the lights are off - like when you're in bed - which is one of the most common use cases. Images of options in phone settings: http://imgur.com/a/lyq6q http://imgur.com/a/lyq6q