This is a music App that I discovered that you can download on your Japanese 3DS via the eshop. This is a free app in which you can buy songs and listen to the latest j pop song clips before you buy!
I was looking through the eshop for my Japanese 3DS and I came across this App. It is a Manga/Book browser in which you can buy books and read them on your 3DS! The App is free but the books obviously are not.