the brain training game
... Brain training ...
So, the #1 game in Japan is a non-game.
My (shocking) conclusion: there is a huge market for new styles of games and new game players, and the gap between "games" and "apps" is getting smaller
1. There's an existing brain-training boom in Japan.
2. The Japanese don't necessarily attach stigmas to "childrens" activities.
3. It's priced really well.
4. Really, it's a fiendish trojan horse.