Katy Perry 's been previewing tracks from her upcoming album, Prism, one by one for the last few weeks, but now the full track list for the album has been revealed on iTunes.
In addition to the single "Roar," the preview tracks "Dark Horse" and "Walking on Air," and the song rumored to be the next single, "Unconditionally," the track listing also includes "Spiritual," a song that Katy's boyfriend John Mayer co-wrote; a song called "It Takes Two," which features John on guitar; "Ghost," which was inspired by her split with Russell Brand , and the ballad "By the Grace of God," which details her suicidal thoughts after her marriage to Brand fell apart.
Katy debuted "By the Grace of God" live on Monday at the iTunes Festival in London. Among the lyrics: "Thought I wasn't enough/ Found I wasn't so tough/ Laying on the bathroom floor/ We were living on a fault line/ And I felt the fault was all mine/ Couldn't take it anymore."
Here's the full track listing for Prism , due October 22:
"Walking on Air"
"Dark Horse" (featuring Juicy J)
"This Is How We Do"
"By the Grace of God"
"It Takes Two"
"Choose Your Battles"
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