According to a Telegraph report, doctors at Chonnam National University Hospital in Seoul found that heavy smartphone use has led to children becoming cross-eyed.
Strabismus, commonly known as cross-eyed or wall-eyed, is a vision condition in which someone cannot align both eyes simultaneously under normal conditions.
One or both of the eyes may turn in, out, up or down.
According to the team, children are holding smartphones at a distance of between eight and 12 inches from their faces.
The team found that the eye condition in nine out of 12 children was treated successfully when they avoided smartphones for nearly two months.
According to the researchers, users should not look at a smartphone screen for over 30 minutes at a time.
"Children showing signs of deviated eyes should consult a doctor immediately," they added.