Before there were smartphones, Japanese people simply carried clamshell mobile phones. They were a bit harder to walk and send email with due to a small screen. People—most infamously schoolgirls—did it. Reading emails and websites was more difficult, too.
Smartphones, however, make it easier to do both. There appear to be more and more people staring at their smartphones. That's exactly why more people are falling into train tracks.
If you've ever been to a train station in Japan, you know that many of the platforms do not have barriers to separate them from the tracks (something that's true in other countries).
Some busy train stations that apparently have experienced high suicide incidents do have barriers—not all, though. The Osaka Monorail has a barrier, because so many of the stations are open air and elevated above roads and freeways.
The majority of people who fall onto the train trains are drunk—so if you or a friend are totally blitzed, a cab might be your best option. The number of these incidents skyrockets in Dec. and Jan. because of year-end drinking parties as well as the New Year holidays.
According to Yoimuiri Online, the country's Ministry of Land, Infrastructure, Transport and Tourism warned that the increase of those falling on the tracks while using smartphones stands out.
Train platforms have yellow, bumpy pathways to help blind passengers board trains. Anecdotally, friends of mine say that when using their smartphone and walking, they know they're near the platform's edge, when they hit said yellow line.
The increase in people falling into train tracks while using their smartphones does seem related to the increase in smartphone use. The iPhone, which initially was not popular in Japan, has caught on in a major way, snagging 72 percent of the smartphone market by spring 2010.
Out went the clamshell design and Japanese companies and carriers began offering their own smartphones to compete with Apple's iPhone. Japan's trains already have posters warning passengers about boarding trains while looking at mobile phones and Nintendo DSi handhelds. Only a matter of time before there are warnings about walking.