questionAnswered: function() {
  var date = new Date();
  var dateStr = date.yyyymmdd();
  cc.sys.localStorage.setItem('lastQuestionAnswered', dateStr);
},

answeredToday: function() {
  var date = new Date();
  var dateStr = date.yyyymmdd();
  return cc.sys.localStorage.getItem('lastQuestionAnswered') == date;
},