Do Swift-based applications work on OS X 10.9/iOS 7 and lower?
I just tested it for you, Swift applications compile into standard binaries and can be run on OS X 10.9 and iOS 7.
Simple Swift application used for testing:
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool { self.window = UIWindow(frame: UIScreen.mainScreen().bounds) var controller = UIViewController() var view = UIView(frame: CGRectMake(0, 0, 320, 568)) view.backgroundColor = UIColor.redColor() controller.view = view var label = UILabel(frame: CGRectMake(0, 0, 200, 21)) label.center = CGPointMake(160, 284) label.textAlignment = NSTextAlignment.Center label.text = "I'am a test label" controller.view.addSubview(label) self.window!.rootViewController = controller self.window!.makeKeyAndVisible() return true}