ionic Application Error – The connection to the server was unsuccessful. (file:///android_asset/www/index.html)
Ionic 2 Angular 2 Cordova Fix: Application Error – The connection to the server was unsuccessful. (file:///android_asset/www/index.html) http://dlvstudio.blogspot.hu/2017/03/hello-world.html
https://forum.ionicframework.com/t/application-error-the-connection-to-the-server-was-unsuccessful/67584/7