Code demonstrated how to load local files into WKWebView - Result works in Simulator, not on device (Tested with 8.2, iPhone 6)

WKWebview local file

// Code wor
import UIKit
import WebKit

class ViewController: UIViewController, WKScriptMessageHandler {

    var webView = WKWebView()
    var contentController = WKUserContentController()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        var path = NSBundle.mainBundle().pathForResource("index", ofType: "html")
        var url = NSURL(fileURLWithPath: path!)
        //var request = NSURLRequest(URL: url!)
        var text = String(contentsOfFile: path!, encoding: NSUTF8StringEncoding, error: nil)
        var theConfiguration = WKWebViewConfiguration()
        contentController.addScriptMessageHandler(self, name: "callbackHandler")
        
        theConfiguration.userContentController = contentController

        webView = WKWebView(frame: self.view.frame, configuration: theConfiguration)
        //webView.loadRequest(request)
        webView.loadHTMLString(text!, baseURL: url)
        self.view.addSubview(webView)
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    func userContentController(userContentController: WKUserContentController, didReceiveScriptMessage message: WKScriptMessage) {
        if(message.name == "callbackHandler") {
            println("JavaScript is sending a message \(message.body)")
        }
    }
}