Mobile commerce is growing, and the creation of mobile-optimized websites is a necessity for many online merchants. But creating a mobile site may cause confusion among consumers if the site ranks poorly in search results, or if it exists in conjunction with the regular, non-mobile version.
There are search-engine-optimization best practices, in other words, regarding the creation and development of mobile sites. We asked Stephan Spencer to describe these to us. He’s vice president of search strategies for Covario, a search engine marketing company for large retailers. He’s also the longtime SEO contributor to Practical eCommerce, the companion publication to Ecommerce Developer.
Ecommerce Developer: Google has a separate mobile-optimized site. Are the organic search results from that site different than from Google's regular non-mobile site?
Stephan Spencer: "No. From all the testing I have done, I have not found any real differences in rankings. There used to be a benefit in having a mobile optimized site, but that no longer appears to be the case. In fact, from my testing, a mobile optimized site is unlikely to rank highly in Google mobile search."
ECD: Why is that?
Spencer: "Well the main site (www.yourcompany.com) is the one that has all the PageRank; that's where everybody's linking to. So a mobile optimized site like m.yourcompany.com is not going to rank as well because it doesn't have nearly as much PageRank as the main site."
ECD: Any idea on what percentage of Google’s visitors uses its mobile optimized search? We know it’s small, but have you seen those numbers?
Spencer: "I have not seen those numbers, I do recall seeing or hearing something about how the majority of Google mobile searches are done from iPhones. I don’t know where that stat comes from but it was pretty interesting at the time. I guess it's so easy to search on an iPhone in comparison to other mobile devices that iPhone users are searching all the time."
ECD: Is there a concern on duplicate content if a merchant has a mobile optimized site and a regular, non-mobile site?
Spencer: "Depends on how it's done. Having the two sites set up as separate URLs, such as m.yourcompany.com and www.yourcompany.com, could very well lead to duplicate content in the index. However, best practice is to have one canonical URL for each page of your site, not two. Have a mobile-optimized site; just don't stick it at a different URL from the regular non-mobile version (no dot mobi, "m" or "mobile" subdomain, or "mobile" subdirectory). With a mobile-optimized site, less is more. Have less content on your mobile pages, less navigation, less legalese. And, this is important: You don’t just use cascading style sheets (CSS) to hide some of the content for mobile users because then the page downloads really slowly (all the bloat is still there in the HTML -- just hidden). It's not just about displaying sparser, more streamlined content to the mobile browser; it's about stripping the excess away before sending the HTML down the pipes."
ECD: So developers should not transfer the unused content or code to the mobile optimized version. The best practice is to strip out anything that the mobile device doesn't use, server-side. But how do you get from there to the canonical URL?
Spencer: "Well, the canonical URL is the one that's loading. So, for example, if I go directly to a category page, like www.yourcompany.com/some-category.php, that page would load in your standard web browser as a regular web page. However, that same URL would load as a sparser, mobile optimized web page if you sent your request from a mobile device. The URL is no different, only the amount of content per page would differ. A product link on that hypothetical category page would lead to the same URL whether you're coming in through a regular browser and seeing a wholly rendered page, or you're on a mobile device and seeing the mobile optimized version. It's the same URL that you're going to. The magic happens when the web server detects the user agent and decides to send out the content optimized for that user agent (or browser). It's going to send the mobile optimized version or the regular web version.
"When a web browser makes a request for a web page, the ‘user agent’ is part of the information that's sent with the request. Just like the referring URL is. That's how web analytics programs know where all your users came from (e.g. which engine) and what keywords they typed in to get there. It's all part of the HTTP header that's sent when the browser makes a request."
ECD: Many mobile optimized sites are stripped of video and audio and other rich media features. Does the removal of these features make that mobile optimized site less SEO friendly?
Spencer: "No, because the search engine spiders are not coming in to a mobile version of the site, assuming you are applying the best practice approach I just outlined. You serve up the regular web pages to Googlebot. It's only the mobile devices that get the stripped down version. All that rich media content is going to be presented to anybody on a regular computer, and to all the search engine spiders. So there's no SEO impact there."
ECD: What SEO tips do you have for mobile-optimized sites?
Spencer: "If you have a mobile site at a separate location or URL, you should 301 redirect each and every mobile page to its corresponding page on your main website. Employ user agent detection so that the mobile optimized version is served up if someone's coming in from a hand-held. If I type in www.yourcompany.com on a Blackberry, I want to see your Blackberry-optimized version. If I'm on an iPhone, I want to see the iPhone version. Don't make your user think. Just serve up the right version in the first place. If I'm savvy enough to type in m.yourcompany.com or mobile.yourcompany.com looking for your mobile version, I should still get your mobile-optimized version, but because I got 301 redirected to www.yourcompany.com then user agent detection kicked in and served me the appropriate version for my device.
"Here's an example of what not to do for SEO, namely to give the engines multiple versions of your site to crawl, such as a mobile version, iPhone version, regular version. This example comes courtesy of one of my favorite weather sites on the web: Weather Underground. Let's say you query for "weather underground" in Google mobile search on the iPhone. You're going to see that the main www.wunderground.com website ranks number one in the results. If you scroll, you'll discover the mobile optimized site that uses a different URL (m.wund.com) also in the results. Scroll further and you'll finally find the iPhone-optimized version (i.wund.com) at number six. That's clearly not ideal because the most appropriate version, the iPhone version, is pretty low in the results. It's unlikely that I'm going to click on that listing. I'm just going to click on the first one that I see. And it's duplicate content to boot. That iPhone user is most likely going to click on the first listing that appears relevant, i.e. the main www.wunderground.com website. At least the iPhone user is presented with a message (although it's only once the page is mostly loaded and rendered on the screen); this message alerts iPhone users to the fact an iPhone-optimized version exists. If I had to scroll down to the bottom of the results to see that there's an iPhone version, and if it was only through clicking that sixth result that I could get to the version optimized for my iPhone, I would not be a happy camper."
ECD: So the main tip is use 301 re-directs to avoid two or three separate sites in the search results. Anything else?
Spencer: "That's the main thing. You'll minimize duplicate content, you'll minimize PageRank dilution, and you'll ensure users on mobile devices will get your mobile optimized site regardless of whether they come in through a mobile URL or a regular, web URL."
