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Make your Site Mobile Friendly

The number of mobile devices loose in the world greatly exceeds the number of desktop (or laptop) computers filling up desk and table space in offices and homes. The number of people who might view your site while clutching a screen measuring anywhere from 100 pixels to 640 pixels in width increases daily. Creating mobile-friendly content is quickly becoming less of an occasional add-on and more of a standard practice.

This article will take a look at how you can create mobile-friendly content, how you can test your work, and offer a few tips for writing CSS for the media type handheld. If you are a Dreamweaver or Flash user, we’ll also take a look at something new from Adobe that will help you test your pages for handheld devices.

Start with the basics

If you begin with standards-based HTML that is formatted with logical, semantic markup, you’re ahead of the game already. A well structured document with clear organization and semantic markup will display cleanly, be usable, and be accessible on any device – mobiles included. Using CSS to separate content from presentation means your content will be accessible, even on the least capable mobile device. Pay attention to other basics as well. For example, good alternative text is an essential for any non-text element in your pages. Make sure that form fields are properly labeled.

Clean, semantic markup is crucial when you consider the variety found in mobile devices. Some phones may only understand WAP. More capable phones may understand WAP2, which opens them up to rendering websites with XHTML and CSS. Some devices may display only monochromatic screen colors, while others may have full color. Some devices support CSS, some do not. Some only understand HTML 3.2, while others understand XHTML. Some devices undertand tables, floats, frames, JavaScript, and dynamic menus, but many do not. Most devices don’t support cookies. Devices at the high end of the mobile market such as BlackBerry, Palm, or the upcoming iPhone are highly capable and support nearly as much as a standard computer.

All those possibilities are enough to make you long for the days when the browser wars meant coding for Internet Explorer 4 or Netscape Navigator 4! But we have two things now that we didn’t have in the bad old days: a large body of knowledge about how to write standards-based HTML and XHTML using semantic markup and about how to separate content from presentation with CSS. If you stick to best practices in those two areas, the need to worry about every single rendering possibility from mobile devices diminishes and you can develop with confidence.

Testing your site

None of the free or fee-based testing options can equal the testing results you get with an actual device. I recommend testing with real mobile devices much as possible, but I know it isn’t feasible to run out and buy every single mobile device. There are some fairly reliable ways to test your site without going to that extreme. Some of the testing techniques are free, some are not. First, let’s look at the free options.

Opera provides two good testing tools. Using the standard Opera browser, select View > Small Screen to see your page rendered in an approximation of what a mobile screen might display. The Opera web developer bar has a button called Display that allows you to toggle CSS on or off when viewing a page using small screen view. Here you see two Opera small screen views of my blog, Web Teacher, first with CSS, then without.

As you can see, Opera renders the images in small screen view. (We’ll talk more about images later.) Note that the small screen view renders the content in source order, that is, the order in which the elements appear in the HTML. Elements are clearly distinguishable from a semantic viewpoint: headings, links, paragraphs, blockquotes. The organizational and semantic underpinnings hold up so that the content is readable and useable. This is especially easy to see in the second screen shot, with the CSS toggled off. Keep in mind that neither of the displays in the previous two screen captures are influenced by a handheld CSS media type stylesheet. When a heldheld CSS stylesheet is present, Opera’s small screen view will take it into account. More about this in a bit.

Opera provides a free browser that can be downloaded and installed on handheld devices. It’s called Opera Mini. (You can purchase Opera Mobile for even more capability.) Both are available at Since Opera is in the business of providing browsers for mobiles, the company made a helpful online mobile simulator at Here, you can load a page into the Mini Demo and operate it with mouse or keyboard as if it were a real mobile phone. The screen capture shows that the Mini Demo renders images and CSS. Again, there is no handheld CSS media type stylesheet affecting this rendering.

Another free way to test your site for clear structure, organization, and proper semantics is with Firefox’s Web Developer extension. Use this tool to disable images, JavaScript, and CSS and you’ll have a good idea about whether your content is going to make sense and be navigable in one of older and less capable mobile phones.

Here’s a Firefox screen capture. For this, the Web Developer Toolbar was used to disable all CSS, all JavaScript, and all images.

Viewing the page without images and with no functioning JavaScipt is very useful in terms of testing for older mobile devices. Keep in mind that some of the less capable mobile devices don’t render tables. None of them understand frames. Seeing your site this way really drives home the importance of standards-driven, semantic markup.

Using specific emulators

Some of the phone and PDA manufacturers have emulators on their sites that you can download and use for testing. Depending on your target audience, testing on a specific emulator might be helpful. If you are interested in specific device or manufacturer, check their site for developer resources. (For example, Sony Ericsson’s Developer World, Nokia has a developer forum with an XHTML section,

Testing CSS Handheld media stylesheets

An important tool in the Firefox Web Developer Toolbar is CSS > View CSS by Media Type > Handheld. If you look at Web Teacher in a standard monitor, you see that it is a simple two column layout using a left float for the content div and a large margin-left to create the sidebar as a second column. I’ll add a stylesheet for handheld media to the testing mix. It contains only two rules — to reset the sizes of the content div and sidebar div and to remove the float. Here’s the entire stylesheet:

#content {
	float: none;
	width: 95%;
#sidebar {
	width: 90%;
	margin-left: 5%;

The link to this stylesheet was added to the document head after the all media stylesheet, so as to be last in the cascade. I’ll use a link element for this. For those mobiles that do understand CSS, using link is more reliable than using @import for bringing in styles, although some of the more capable devices understand @import. Here’s the link element:

Media types are mutually exclusive. A user agent can only support one media type when rendering a document. If I want to retain any of my existing styles in a handheld display, I need to take one more step, and that is to list all the media types I want my existing styles to apply to in a comma separated list. I change the link element for my existing stylesheet, which is called 2col.css to include this media attribute: media="handheld,all". The two link elements are now:

The styles and the color scheme I have in 2col.css should also apply to handheld renderings, but the two column layout will be removed by the mobile.css rules.

Testing with the Firefox Web Developer Toolbar menu CSS > View CSS by Media Type > Handheld should now show handheld media results, and it does.

The first screen capture shows the two column layout, as it normally displays with the all media stylesheet. The second shows Firefox using the handheld media view.

From the second screen capture, you can see that Firefox has expanded the content div to 95%, according to the mobile.css rules. If you scrolled down the page past the content div, you would find the sidebar div now displays at 90% width after the content div. Note in the second screen capture, that styles from 2col.css such as the presentation of the list under the title image and the background gradient behind the headings are retained because of the handheld media designation in that stylesheet.

You may not want to retain any of your all media styles in the handheld CSS rules, as in this example. Keeping the background images, for example, results in longer page load times. Since many wireless mobile devices load very slowly, you want to really simplify things for handhelds. In that case, simply leave the handheld media attribute out of your main stylesheet. I’ll give you more tips for simplifying things for handheld media shortly.

Testing with subscription services or with software

The testing tools I just mentioned are all free. There are other options that are not free, but you might find them helpful and worth the expense. Browser Cam, where you can test your sites in all sorts of browsers, has added a testing area called Device Cam. Here you can test a page in a smattering of Windows Mobile-based PDAs and several BlackBerry versions. Here’s a screen capture of the test page in a Device Cam rendering of a BlackBerry. Note the strong resemblance to what you saw previously in Opera’s small screen view when the CSS was toggled off.

A brand new option for owners of Adobe’s latest CS3 software is Adobe’s Device Central. Device Central uses skins for dozens of mobile devices to display your content in various ways. Here’s a rendering of the test page in a Nokia 7390 skin.

Device Central can load a live URL or a file from many of the Adobe CS3 applications. It responds to the presence of a stylesheet of the handheld media type when the page is rendered using Opera’s small screen view. Using the Opera small screen view is an option with each of the skins in Device Central. Deselecting the option to view the rendering with Opera’s small screen view in Device Central rendered this page as two columns, in spite of the presence of the handheld stylesheet rules meant to eliminate that.

Tips for handheld CSS

Handheld media stylesheets can be more extensive than the two rule example I showed you previously. A few more rules would certainly benefit Web Teacher, but keep in mind that handheld stylesheets should be as small and compact as possible because of download time.

What can you do to simplify your site and make it more usable in mobiles? First, eliminate some of these problematic items from mobile display.

Once you’ve simplified through elimination, start building the rules you need to add. Consider these ideas.

Tips for bloggers

Some blogging software provides the opportunity to format a single blog posting with several different templates, one of which can be meant for mobile users. This specially formatted and simplified material is posted to a unique URL on your site, perhaps something like If you’re a blogger, check your software to see if you have this capability with your blog. One important consideration for the mobile users of your blog is to keep the number of blog postings per page to a minimum for faster downloads.

In summary, making your site mobile friendly can be boiled down to a few concepts. Use validated, standards-based HTML or XHTML, ensure meaningful semantic markup with presentation removed to a stylesheet, and add handheld media rules as needed.

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