A high-ranking official from the World Health Organization (WHO) believes that countries should consider restricting how young people use smartphones and other handheld devices. Dr. Natasha Azzopardi-Muscat, who leads a part of the WHO focused on health policies, likened the overuse of these gadgets to being addicted to tobacco.

At a recent health forum in Austria, she suggested that just like smoking bans in certain places, we might need to think about where and when it’s okay to use sm...