Owning a smartphone may not be as smart as you think. They may let you surf the Internet, listen to music and take photos wherever you are, but they also turn you into a workaholic . A study suggests that, by giving you access to emails at all times, the smartphone adds as much as two hours to your working day. Researchers found that Britons work an additional 460 hours a year on average as they are able to respond to emails on their mobiles. The study shows the average UK working day is between 9 and 10 hours, but a further 2 hours is spent responding to or sending work emails, or making work calls. Almost one in ten admits spending up to three hours outside their normal working day checking work emails. Some workers say they are on call almost 24 hours a day. Nearly two-thirds say they often check work emails just before they go to bed and as soon as they wake up, while over a third have replied to one in the middle of the night. The average time for first checking emails is between 6 am and 7 am, with more than a third checking their first email in this period, and a quarter checking them between 11pm and midnight. Ghadi Hobeika, marketing director of Pixmania, said: "The ability to access millions of applications has made smartphones invaluable for many people. However, there are disadvantages. Many companies expect their employees to be on call 24 hours a day, seven days a week, and smartphones mean that people cannot get away from work. The more constantly in touch we become, the more is expected of us in work . " With a smartphone the average UK working day is   _  .
2 hours 9 to 10 hours 11 to 12 hours 24 hours