iPhone “Bookmark to Homescreen” removes cookies an

Question

Right now I am developing a Web-based Application, where the User has to login first.

When I open the Page by iPhone Safari, login and restart Safari, I am still logged in (Cookie & Session ID still set).

But when I add this Page with "Add to Home Screen", each Time i click the Icon for that page, I have to login again.

I did not find any information about that. What can I do so my users can set this page to their home screen as icon and still don't have to login each time they open it?

Answer 1

I am going to expand a little further on Waldo Baggins' answer.

When I ran into this, I discovered the reason this was happening is that session cookies set on the server usually do not have an expiration value set. The default behavior in this case is for the browser to discard the cookie when the browser is closed / re-opened. Since the browser does not resend the cookie on re-opening, the server has no way of identifying the session, even if it hasn't expired on the server yet, and thus, your user is redirected back to the login page.

When the user is using your site in web app mode (icon added to home screen), iOS treats navigating to / from the app the same way a desktop computer would treat closing and reopening the browser, and loses the session when reopened.

So following Wilbo's suggestion and setting an expiration time for the cookie, iOS checks if the cookie has expired when the user navigates back to your app, and if it hasn't, re-sends the cookie, thus maintaining the session. The value of 1 year in Wilbo's answer is ridiculously long, you would typically want to set this to something like 8 or 24 hours, and ideally sync it with the session expiry timeout value you have set on the server.

Note that as a side effect, when your site is accessed from a desktop browser, and the user closes and re-opens the browser, the session would continue to persist and the user will still be logged in, which wouldn't have been the case previously (unless they were browsing privately). Your "Logout" feature would have to properly handle expiring this cookie.

For a Java webapp using web.xml version 3.0 or higher, the easiest way to do this is to modify <session-config> as follows:

<session-config>
    <session-timeout>600</session-timeout> <!-- In minutes -->
    <cookie-config>
        <http-only>true</http-only>
        <secure>true</secure>
        <max-age>36000</max-age> <!-- In seconds -->
    </cookie-config>
</session-config>

Answer 2

There is an easier and, imo, more elegant solution than favo's.

At least under iOS 4.2.1, 5.1.1, 6.0 and 6.1 (I couldn't test other versions), if you extend the lifetime of your session cookie manually, Safari will hold on to the session cookie and even allow sharing of the session between the 'home screen installed' version of your web app and normal visits through Safari itself.

The trick is to do this:

// Start or resume session
session_start(); 

// Extend cookie life time by an amount of your liking
$cookieLifetime = 365 * 24 * 60 * 60; // A year in seconds
setcookie(session_name(),session_id(),time()+$cookieLifetime);

For a more elaborate discussion of this strategy you can take a look at my answer of this question:

Maintain PHP Session in web app on iPhone

Answer 3

There are persistent key-value storage and database storage available for web apps. You can save your authentication data using localStorage object and use XMLHttpRequest to send it to the server. Another option is saving your persistent data in a SQLite database, however this doesn’t seem to be a proper solution in your case. Check out Apple’s Client-Side Storage and Offline Applications Programming Guide for details/examples.

Answer 4

A really simple approach could be to use a unique token in your Bookmark-URL which can serve you as a unique device identifier.

Example: http://myWebApp.com/?token=randomId29238/1

The token can be generated at the server side at opening time of the application in Mobile Safari and before the user is prompted with the "Add to Home Screen" information. The token can then be added to the URL using a quick redirect (…&token=randomToken) or a location hash (…#randomToken).

Whenever the Bookmark is now opened from the Home Screen, the token is sent to your server and you can identify the user's active session. You may also use the token as a permanent session id, but I advise against that because of security concerns.

To allow future logout and login procedures, you can always assign the new sessions to the token.

The token will serve you as a unique device identifier whenever the user will re-open your link from his Home Screen.