Utatchi

"Utatchi (うたっち) is a rhythm video game developed and published by Konami for the Nintendo DS handheld game console in 2010, and it was released only in Japan. It is credited as a release under the Pop'n Music brand. The game plays with the DS held "book style" and the player interacts with falling notes using the stylus." Source: Wikipedia, "Utatchi", available under the CC-BY-SA License.