Nearly two-thirds of senior high school students spend at least two hours a day tapping their smartphones, messaging buddies, reading news or just aimlessly surfing.

More precisely, 63.3 percent spend two hours or more online, while 11.4 percent lose at least five hours a day glued to their phones, a government survey showed on Wednesday. The average user tinkered around online for 154.6 minutes a day.

Many are chained to other devices, too. If you include online use from a personal computer or gaming console, 18.9 percent of senior high school students spend at least five hours a day on the Internet, the Cabinet Office survey showed.