For the first time in three years, the number of mobile phones recycled in Japan was down in fiscal 2011, a reflection of the tendency of people to hang on to their handsets even after canceling their contracts, according to the Telecommunications Carriers Association.

Ever since Softbank Mobile Corp. began selling Japan's first smartphone, the iPhone, in July 2008, the trend has been to keep old models as data-storage devices. The number of recycled mobile phones dropped 5.1 percent to 6.97 million units in the year that ended in March, from 7.34 million a year earlier, the association said in a release Tuesday.

"With the prevalence of smartphones, mobile phones have high-tech and many functions. Thus, more people keep phones that they no longer use as communication tools," the association said.