More than half of Hong Kong’s underprivileged children spend more than two hours a day on electronic devices, many of them turning to screens as cheap entertainment despite problems with their eyesight, attention, sleep and addiction, a survey by a community group has found. The Society for Community Organisation (SoCO), which released the findings on Sunday, urged authorities to keep students on campus for longer, introduce full-day kindergartens and subsidise more extracurricular activities...