Mimicking the Things.app 3.0 status bar tinting

AppDelegate.swift

import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?
    var overlayWindow = UIWindow()

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {

        overlayWindow.frame = CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 20)
        overlayWindow.windowLevel = UIWindowLevelStatusBar
        overlayWindow.backgroundColor = UIColor(white: 1, alpha: 0.4)
        overlayWindow.rootViewController = UIViewController()
        overlayWindow.isHidden = false
        
        return true
    }
}