Google recently announced on their Webmaster Central blog that “we will be expanding our use of mobile-friendliness as a ranking signal. This change will affect mobile searches in all languages worldwide and will have a significant impact in our search results.” And, announced that they would be using more indexed content from apps in search results (which they’ve already started doing). The update is called mobilegeddon, mobilepocalyse, mobocalypse or mopocalypse.

Generally, mobile website can be runs in one out of three configurations — responsive web design, dynamic serving and separate URL’s.

Responsive Web Design

It serves the same HTML code on the same URL regardless of the users’ device, including desktop, tablet, mobile and non-visual browser. But it can render the display differently based on the screen size.

Dynamic Serving

It is a setup where the server responds with different HTML code on the same URL depending on the user agent requesting the page.

Separate URL’s

In this method different URLs are being served to users. For example, mobile sites are built on a subdomain, m.domain.com – or if you have a private blog network with a variety of subdomains as money pages. It means that both desktop and mobile versions are being developed for a website and being served to the user according to their device.

Time to Prepare for Mobilegeddon

Google may have announced the update early. But the update hasn’t exactly been forthcoming with details. Google Webmaster trends analyst Gary Illyes did share a few details in a recent Q&A.

Most significantlly:

Responsive web design does not have a ranking benefit

Google’s web crawler Googlebot must be allowed to crawl CSS & JavaScript to pass the “mobile-friendly” test

Mobile-friendly test is determined at the page level – not sitewide

This update does not affect tablets.

Google is now working on a dedicated mobile index

The infographic below was created by Nine Hertz. It comes with lots of helpful mobile SEO advice, including the common mistakes and recommended actions to make sure that your mobile site is search-engine friendly.