Auto detect mobile browser (via user-agent?) [clos

Question

How can I detect if a user is viewing my web site from a mobile web browser so that I can then auto detect and display the appropriate version of my web site?

Answer 1

You can check the User-Agent string. In JavaScript, that's really easy, it's just a property of the navigator object.

var useragent = navigator.userAgent;

You can check if the device if iPhone or Blackberry in JS with something like

var isIphone = !!agent.match(/iPhone/i),
    isBlackberry = !!agent.match(/blackberry/i);

if isIphone is true you are accessing the site from an Iphone, if isBlackBerry you are accessing the site from a Blackberry.

You can use "UserAgent Switcher" plugin for firefox to test that.

If you are also interested, it may be worth it checking out my script "redirection_mobile.js" hosted on github here https://github.com/sebarmeli/JS-Redirection-Mobile-Site and you can read more details in one of my article here:

http://blog.sebarmeli.com/2010/11/02/how-to-redirect-your-site-to-a-mobile-version-through-javascript/

Answer 2

You haven't said what language you're using. If it's Perl then it's trivial:

use CGI::Info;

my $info = CGI::Info->new();

if($info->is_mobile()) {
   # Add mobile stuff
}

unless($info->is_mobile()) {
   # Don't do some things on a mobile
}

Answer 3

Just a thought but what if you worked this problem from the opposite direction? Rather than determining which browsers are mobile why not determine which browsers are not? Then code your site to default to the mobile version and redirect to the standard version. There are two basic possibilities when looking at a mobile browser. Either it has javascript support or it doesn't. So if the browser does not have javascript support it will default to the mobile version. If it does have JavaScript support, check the screen size. Anything below a certain size will likely also be a mobile browser. Anything larger will get redirected to your standard layout. Then all you need to do is determine if the user with JavaScript disabled is mobile or not.
According to the W3C the number of users with JavaScript disabled was about 5% and of those users most have turned it off which implies that they actually know what they are doing with a browser. Are they a large part of your audience? If not then don't worry about them. If so, whats the worst case scenario? You have those users browsing the mobile version of your site, and that's a good thing.

Answer 4

Yes user-agent is used to detect mobile browsers. There are lots of free scripts available to check this. Here is one such php code which will help you redirect mobile users to different website.

Answer 5

Have you considered using css3 media queries? In most cases you can apply some css styles specifically for the targeted device without having to create a separate mobile version of the site.

@media screen and (max-width:1025px) {
   #content {
     width: 100%;
   }
}

You can set the width to whatever you want, but 1025 will catch the iPad landscape view.

You'll also want to add the following meta tag to your head:

<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1">

Check out this article over at HTML5 Rocks for some good examples

Answer 6

There are open source scripts on Detect Mobile Browser that do this in Apache, ASP, ColdFusion, JavaScript and PHP.