ReplayKit.swift

func runBroadcast() {
    // Step 1
    RPBroadcastActivityViewController.load { broadcastAVC, error in
        // Step 2
        guard error == nil else {
            print("Cannot load Broadcast Activity View Controller.")
            return
        }

        // Step 3
        if let broadcastAVC = broadcastAVC {
            broadcastAVC.delegate = self
            self.present(broadcastAVC, animated: true, completion: nil)
        }
    }
}

func stopBroadcast() {
    controller.finishBroadcast { error in
        if error == nil {
            print("Broadcast ended")
        }
    }
}