iOS Detection

  function iOSversion() {
    if (/iP(hone|od|ad)/.test(navigator.platform)) {
      var v = (navigator.appVersion).match(/OS (\d+)_(\d+)_?(\d+)?/);
      return [parseInt(v[1], 10), parseInt(v[2], 10), parseInt(v[3] || 0, 10)];
    }
  }

  var ver = iOSversion();

  if (ver[0] >= 7 && ver[0] < 8) {

    $('html').addClass('ios7');

  }