On April 21st, Google made an enormously important change to its algorithms, which significantly magnifies the use of mobile-friendly sites as a ranking signal. For retailers, that means that if their site lacks responsive design, it is far less likely to show up in search results.

In explaining the move on its official Webmaster blog, Google said that, “users will find it easier to get relevant, high quality search results that are optimized for their devices.”

That mobile search engine optimization (SEO) is now a “thing” of its own is not particularly surprising. The Demandware Shopping Index recently revealed that smartphones accounted for 33% of ecommerce traffic and 16% of orders. Further, the Index found that 21% of shoppers use multiple devices to complete an online purchase.

Responsive design is one critical way that merchants can create a positive user experience. A 2014 article on HubSpot noted that a great mobile experience is “a necessity and literally impacts the growth of your business.”

So what do retailers without responsive websites need to do? Google offers a free tool to help retailers determine if their sites are mobile-friendly. Click here to use the tool. Here are other important considerations:

Quick Fixes
1. Allow indexing of Javascript, CSS and images. You can do this by ensuring your robots file is not set to disallow these assets.

2. Use Google Webmaster to test that both desktop and mobile URLs are crawl-able and don’t result in any errors.

3. Make sure all your URL redirects are valid (no errors – check Google Webmaster).

Design Fixes
1. Avoid proprietary content players (e.g. Adobe Flash) since they don’t always render on mobile devices.

2. Use responsive design when possible (Demandware helps here by providing a reference implementation that’s responsive design compliant)

3. If you have links in your desktop site page pointing to the mobile site (and vice-versa), make sure these links point to its corresponding peer and not a generic page like, for example, the home page.

4. Use Google PageSpeed Insights to discover if your site has any issues that can slow page load times. If there are, fix them.

It’s no secret that mobile devices are exploding as Internet access points, and that smartphones are an integral part of the evolution to omni-channel retailing embraced by merchants worldwide. Google’s new ranking methodology will further hasten development of mobile capabilities.