The eight chapters in the free version included an introduction to hiragana, chapters on greetings and a cultural interlude on the geography of Japan.

WSJ: Mobile Apps for Foreign Languages

It also has plans to add an early-warning radar system in western Japan, while South Korea has pledged to speed up the introduction of its own missile defense systems.

WSJ: North Korea Moves Missile to Its East Coast

The games in Japan saw the introduction of wheelchair racing - although only in the normal day-to-day chairs rather than the space age machines used by the Paralympians of today.

BBC: History of the Paralympics