A condition in which people’s eyes turn inward and make them look cross-eyed is reportedly on the rise in Japan due mainly to excessive and improper smartphone usage, with young people particularly vulnerable.Known as acquired esotropia, the condition is a form of strabismus, or a misalignment of the eyes in which one eye deviates towards the nose and the other remains in its original position.It appears more frequently among young Japanese, who experience double vision and poor depth...