iOS: Detect if the device is iPhone X family (frameless)

You could "fitler" for the top notch, something like:

var hasTopNotch: Bool {
    if #available(iOS 11.0, tvOS 11.0, *) {
        return UIApplication.shared.delegate?.window??.safeAreaInsets.top ?? 0 > 20
    }
    return false
}

Swift 5, iOS 14 supported

Thanks to @Tanin and @DominicMDev, since keyWindow was deprecated in iOS 13 and the iPad Pro has non-zero safeAreaInsets, this works fine for me.

(Already tested on iPhone 8, iPhone 11 Pro and iPad Pro (11-inch)(2nd gen) Simulators)

extension UIDevice {
    /// Returns `true` if the device has a notch
    var hasNotch: Bool {
        guard #available(iOS 11.0, *), let window = UIApplication.shared.windows.filter({$0.isKeyWindow}).first else { return false }
        if UIDevice.current.orientation.isPortrait {
            return window.safeAreaInsets.top >= 44
        } else {
            return window.safeAreaInsets.left > 0 || window.safeAreaInsets.right > 0
        }
    }
}