Ios/swift/アプリを評価

let itunesURL:String = "itms-apps://itunes.apple.com/WebObjects/MZStore.woa/wa/viewContentsUserReviews?type=Purple+Software&id=[アプリid]"
let url = NSURL(string:itunesURL)
let app:UIApplication = UIApplication.sharedApplication()
app.openURL(url!)