Google Search Mobile-First Indexing and eCommerce SEO

Google mobile first indexing

Google Search Mobile-First Indexing and eCommerce SEO

“Larry Page once described the perfect search engine as understanding exactly what you mean and giving you back exactly what you want.” (1)

Google is continuing with its research and development efforts to achieve this goal.   As part of ongoing development, Google regularly introduces modifications to its crawler (Googlebot),  to the search engine algorithm and to the way how the search engine presents results to the end users.

Google made an announcement about the major updates but most of the updates are not announced.  You may find official tweets from Google about search engine updates including algorithms upgrades on the Google Search Liaison twitter page:

So far, in 2018 we can see two announcements about broad core algorithm updates on March 12 and April 20, 2018. In addition on March 26, Google made the official announcement about the rollout of Mobile-first Indexing. According to the announcement published on Google Webmaster Central Blog (2):

“Today we’re announcing that after a year and a half of careful experimentation and testing, we’ve started migrating sites that follow the best practices for mobile-first indexing.”

Google made the first announcement about the transition plan to Mobile-first indexing on November 4, 2016. (3)

What does it mean for eCommerce sites Search Engine Optimization and for overall web SEO?

Here is the Google explanation (4):

“Mobile-first indexing means Google will predominantly use the mobile version of the content for indexing and ranking. Historically, the index primarily used the desktop version of a page’s content when evaluating the relevance of a page to a user’s query. Since the majority of users now access Google via a mobile device, the index will primarily use the mobile version of a page’s content going forward.”

Google will not create a new addition index for mobile devices but will keep only one mobile index. Googlebot will use the mobile agent instead of the desktop agent to crawl and index all websites going forward.
Since the start of the mobile revolution in 2010 majority of website owners either converted their sites to responsive web design, dynamic sites that serve content based on user’s device, or implemented separate mobile sites. However, we still see some websites that have the desktop only version.
Google provides the explanation how different type of website will be affected during the mobile first-rollout (4).

Type of the site

How it is affected by Mobile First Indexing

Desktop only

There is no mobile version or the site

No change. The mobile version is the same as the desktop version.

A desktop-only site has a major SEO disadvantage because the majority of the searches are coming from non-desktop devices. The search ranking of a desktop-only site will likely continue to degrade over time. Adobe Flash and unsupported on mobile video formats will have also a negative impact on search rankings.

Responsive Web Design

Serves the same HTML code on the same URL regardless of the users’ device

No change. The mobile version is the same as the desktop version

The modern popular e-commerce platforms offer responsive web design site themes.

Make sure that your responsive theme passes mobile friendly Google test and provides good score with the Google page speed test to maintain the SEO ranking.

Canonical AMP

All your web pages are created in AMP (Accelerated Mobile Pages) HTML and there are no pages that use other than AMP, HTML.

No change. The mobile version is the same as the desktop version.

Dynamic Serving

Uses the same URL regardless of device, but generates a different version of HTML for different device types

Google prefers the mobile URL for indexing.

Your mobile site should contain the same content as your desktop site including metadata and structured data. You may need to audit both sites and make necessary updates to the mobile site to include all content. If you have dynamics serving e-commerce site make sure that all product information including text, images, videos with alt attributes and metadata as well as product reviews are available in the mobile site version.

Separate URLs

Serves different code to each device, and on separate URLs. This configuration tries to detect the users’ device, then redirects to the appropriate page, for instance,, and

Google prefers the mobile URL for indexing.
If you have a separate mobile URL site you should verify the m-dot site and make necessary changes to make sure that all content, metadata, and structured data are available on both sites.

AMP and non-AMP

Your site has both AMP and non-AMP versions of a page. Users see two different URLs.

Google prefers the mobile version of the non-AMP URL for indexing.

Your action plan depends on the technology that used by the non-AMP mobile version.

Please see above the recommendations for the responsive web design, dynamic serving, and separate URL sites.


Changes to Google search engine reflect the evolution of the web content and users behavior.  Majority of the searches today are coming from mobile devices. Switching to the mobile agent for indexing is a reflection of the significant shift in user behavior since the introduction of the first iPhone in 2007.

Updates to e-commerce sites have to follow the changes in shoppers’ behavior.  Majority of users look for information on their mobile devices and some of them using voice searches. A lot of purchases are started from mobile searches and  some of them are completed on another device.

Now is the right time to conduct your mobile search experience audit and create a plan which updates are required to make sure that the switching to mobile–first indexing does not have a negative impact on your eCommerce site search ranking.  

Igor Nesmyanovich, Ph.D., CISSP

Igor Nesmyanovich, Data Scientist and CEO of Eradium. Igor began his career as a space scientist, and for more than two decades applied the unique art of science to the emerging digital world. Igor is a Certified Information Systems Security Professional since 2004. Today Igor’s focus is on helping clients to accelerate business growth with technology innovations at the intersection of marketing, science, and technology.