Short answers, pulled from the story.
Silent Hill: Book of Memories is a dungeon crawler spin-off of the Silent Hill series, developed by WayForward Technologies and published by Konami. It was released for the PlayStation Vita on the 16th of October, 2012, in North America, with European, Australian, and Japanese releases following through February 2013.
WayForward Technologies developed the game, with Tomm Hulett as producer and Adam Tierney as director. Development began in September 2010. Konami published the title.
The game features six endings in total. Five are serious endings tied to the player's alignment and in-game choices: Pure Blood, Blood, a neutral ending, Light, and Pure Light. The sixth is a joke ending, in the tradition of earlier Silent Hill games, that sends the cast to Silent Hill on spring break.
Daniel Licht, who also scored Silent Hill: Downpour, composed the main soundtrack. Rob King and voice actor Troy Baker co-composed an additional song called "Love Psalm", which featured vocals by Mary Elizabeth McGlynn and was performed by Eyeshine, featuring Akira Yamaoka. The soundtrack was released on the 17th of April, 2012.
Reviews were mixed, with Metacritic classifying the reception as "mixed or average". Some critics found it an enjoyable dungeon crawler that stood on its own merits; others argued it failed both as a Silent Hill title and as a dungeon crawler, describing it as an "identity crisis". The game's RPG elements and suitability for short sessions were praised, while its checkpoint system and late-game difficulty drew criticism.
Book of Memories was deliberately designed to depart from the single-player survival horror format of previous Silent Hill titles. Konami's vision centered on short multiplayer sessions suited to a handheld console. It is the first installment in the main series to feature multiplayer gameplay, aside from Silent Hill: The Arcade.