For your brother Marcus who is primarily obsessed with three things: Nature, Icelandic singers and his iPad: Performer and environmentalist Bjork has always been fairly preoccupied with the natural world (and we’re not just referring to her swan-based attire), and her latest release, “Biophilia,” celebrates the mysteries of Mother Nature full-on. With tracks titled “Thunderbolt,” “Virus” and “Cosmogony,” the album features the lush electronic soundscapes and vocal gymnastics one would expect from Bjork with one notable difference: “Biophilia” was composed partly on an iPad and the album itself was released as a series of 10 interactive apps that Bjork developed with Apple. A man whom Bjork calls her childhood “rock star,” British naturalist David Attenborough, provides narration for this unique iPad experience.