Hyperdimension Neptunia U: Action Unleashed (超次元アクション ネプテューヌU Chō Jigen Akushon Nepute~yūnu U?, lit. Super Dimension Action Neptune U) is a hack and slash video game developed by Tamsoft and published by Compile Heart in Japan and Idea Factory in the west. As a spin-off title in the Hyperdimension Neptunia game series, it was announced by Compile Heart at the 2014 Dengeki Stage Event when the game was being created by Tamsoft who is known for their work with the Senran Kagura and OneChanbara games. The game was released in Japan on August 28, 2014, and in North America and Europe in May 2015 for the PlayStation Vita.
Source: Wikipedia, "[en.wikipedia.org/wiki/Hyperdimension_Neptunia_U%3A_Action_Unleashed Hyperdimension Neptunia U: Action Unleashed]", available under the CC-BY-SA License.