一次将移动用户重定向到应用下载

Question

So most of the time as I am browsing the net if I go to a website that has an app it first takes me to a landing page that says bla bla the site is better on the app download it here or "no thanks". Then after you do that it no longer asks you that question. what is the easiest way to implement this kind of action? Using javascript I can find if a person is on android

var ua = navigator.userAgent.toLowerCase();
var isAndroid = ua.indexOf("android") > -1; //&& ua.indexOf("mobile");
if(isAndroid) {
    // Do something!
    // Redirect to Android-site?
    window.location = 'http://android.davidwalsh.name';
}

However how do I make this only happen one time? which page would I add it to? Any ideas? I was thinking cookie but I am not sure if mobile browsers let you add cookies the same way.

Answer 1

You could set a cookie on the first visit. On the next visit if you detect the cookie you can redirect them immediately. Something like below (untested):

var ua = navigator.userAgent.toLowerCase();
    var isAndroid = ua.indexOf("android") > -1; //&& ua.indexOf("mobile");

    if(isAndroid) {

        if (document.cookie.indexOf("mobile") >= 0) {

             //user has visited already on mobile so redirect immediately 
              window.location = 'http://android.davidwalsh.name';

           } else {

             expiry = new Date();
             expiry.setTime(date.getTime()+1000000); 

             //First time here - show a message, set a cookie and redirect etc.
             document.cookie = "mobile=yes; expires=" + expiry.toGMTString();
             window.location = 'http://android.davidwalsh.name';

            }

        }