Detect screen orientation on iOs

screenOrientationIOs.js

function doOnOrientationChange(){
  switch(window.orientation) {  
    case -90:
    case 90:
      alert('landscape');
      break; 
    default:
      alert('portrait');
      break; 
  }
}

window.onorientationchange = function(){
  doOnOrientationChange();
};

// Initial execution
doOnOrientationChange();

//from http://stackoverflow.com/a/9824480/1409080