Glue to allow you to work with date inputs using the native datepicker when supported and JQuery UI as a fallback

datepicker-html5-glue.js

(function() {
  var setupDatePickerGlue = function($el, format) {
    var elName  = $el.attr("name"),  // field name
        elId    = $el.attr("id"),    // field id
        elValue = $el.attr("value"); // field raw value

    // remove the name to prevent value conflict on submit
    $el.removeAttr("name");
    // prepend an hidden input field with the same name
    $el.before($("<input type='hidden' name='" + elName + "' id='raw-" + elId + "' />"));

    $el.datepicker();
    // set the altField so we update the hidden input on date change
    $el.datepicker("option", "altField", "#raw-" + elId);
    // set the altFormat to update the altField with the given format
    $el.datepicker("option", "altFormat", "yy-mm-dd");
    // if there is a prefilled value, use it
    if (elValue != null && elValue.length > 0) {
      $el.datepicker("option", "dateFormat", "yy-mm-dd");
      $el.datepicker("setDate", elValue);
    }
    // set the desired format
    $el.datepicker("option", "dateFormat", format);
  }

  $(function() {
    if (!Modernizr.inputtypes.date) {
      $('input[type=date]').each(function() {
        setupDatePickerGlue($(this), 'dd/mm/yy');
      });
    }
  });
})();