Geneva, Oct 12 (Prensa Latina) To draw attention to blindness and vision impairment worldwide, every year on the second Thursday of October, World Sight Day is observed. For this year’s celebration, the World Health Organization (WHO) has launched “WHOeyes”, a free app for the general public to check how well they can see things close up and at a distance and learn how they can protect their eyes. The app checks visual acuity – a measure of how well the eye can distinguish shapes and details at a given distance and is the most common assessment of visual function.