JS 判断用户设备是IOS 还是 Android

$(function () {
    var u = navigator.userAgent, app = navigator.appVersion;
    var isAndroid = u.indexOf('Android') > -1 || u.indexOf('Linux') > -1; //g
    var isIOS = !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/); //ios终端
    if (isAndroid) {
        alert("安卓机！")
    }
    if (isIOS) {
        alert("苹果机！")
    }
});