There's a "game" for the 3DS called Honto for 3DS which is a children's e-reader. AFAIK it's a Japan exclusive, and I downloaded it for my Japanese region N3DS after hacking it. That being said, none of the books/manga for it are available anymore. I have found some executable files online, but nothing that I am aware can actually be added to the library via my SD card. Any ideas where I could go to download all the literature for Honto?