get userAgent & version

gistfile1.txt

var ua = navigator.userAgent,
         uaFunc = function(s,h)  { return (h.indexOf(s) > -1)};
var userInfo = {};

if(uaFunc("iPhone", ua)) {
  userInfo.device = "iPhone";
} else if(uaFunc("iPad", ua)) {
  userInfo.device = "iPad";
} else if(uaFunc("Android", ua)) {
  userInfo.device = "Android";
} else {
  userInfo.device = "PC";
}

if(userInfo.device == "iPhone") {
  userInfo.ver = uaGetVer("iPhone OS", "like");
} else if(userInfo.device == "iPad") {
  userInfo.ver = uaGetVer("CPU OS", "like");
} else if(userInfo.device == "Android") {
  userInfo.ver = uaGetVer(userInfo.device, ";");
} else {
  userInfo.ver = null;
}

function uaGetVer(myKey,contextEnd) {
  var myStart = ua.indexOf(myKey) + myKey.length,
      myEnd = ua.indexOf(contextEnd, myStart);

  return "Ver." + ua.substring (myStart,myEnd);
}