Japan was one of the earliest countries to widely adopt phones that could access the internet. But a funny thing has happened there: sales of smartphones have taken a dive. Instead, Japanese consumers are flocking to older styles of cellphone — like the venerable flip-phone.

According to the Japanese newspaper Asahi Shimbun, sales of what have been dubbed "gara-kei," a catchall term for the style of simple screen-keypad cellphone popular before the iPhone, are rising for the first time in seven years. About half of people with cellphone contracts in Japan use gara-kei, which means "Galapagos phone" — a nod to how they have evolved for a peculiarly Japanese market. The phones can have email and basic internet access, with many using the old-school flip design.

Sales of gara-kei increased 5.7 percent over 2014, with smartphone sales, by contrast, falling for a second straight year. The big question, of course, is why.

Takao Shinkai, the Asahi Shimbun writer, suggests price is a major factor. Flip-phone monthly charges are apparently several thousand yen cheaper (1,000 yen is a little over $8.25). But the Japanese economy has been weak for quite some time now, and wage growth is the strongest it's been in 15 years. The economic story has some trouble explaining why smartphone sales are decreasing now.

Forbes' Jake Adelstein, a veteran Japan correspondent, thinks price is part of the story. But he also proposes two other possible explanations. First, Japan has a low birth rate and a large elderly population. Older people might be less likely to use fancy smartphone features as opposed to simple calling and texting, so as the country ages, smartphone use may decline.

Second, flip-phones are simply better at some things than smartphones. Smartphones can be easy to break, as anyone who's shattered an iPhone screen knows. The flip part of a trusty flip-phone, by contrast, shelters the screen and keypad. Smartphones often have frustratingly short battery lives; flip-phones can last for a really long time.

flip-phones are simply better at some things than smartphones

The thing about all of these theories, though, is that nothing about them should apply to Japan only. People everywhere get irritated at the expensive, fragile battery monsters in their pockets. And Japan is hardly the only country with an aging population: South Korea and several western European countries also have graying citizenries, though Japan's problem is particularly acute.

According to Gartner, a leading market research firm, smartphones sales shot up worldwide in 2014. But in December 2014, the firm reported that western Europe was an exception: smartphone sales were down by 5.2 percent, and had declined for three straight quarters. That's pretty consistent with Adelstein's theory: if the decline in smartphone use is about aging populations and fatigue with smartphones' most annoying features, then western Europe is the next logical place to look after Japan.

None of this means smartphones are on the long-term decline, or that smartphone manufacturers are in major trouble. Not even close. But it's fun to think that flip-phones, which feel like they died with the Bush administration, are staging a comeback in one of the world's technology hubs.

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