We’ve had pretty good notice from Google about the shift in the mobile algorithm which is to occur on April 21st. This is touted to be a bigger update then seen with Penguin or Panda. Have you prepared?
There are a number of ways you can check to see if pages (yes, this is on a page-by-page basis) on your site conform with the new requirements.
First, you can run sample mobile searches to see if your site gets the sought after “Mobile Friendly” label in the SERPs. A much easier way to do this is to use the site: command (site:www.yourdomain.com.au) to get a broader view of the pages Google has in the mobile index and which ones contain the label, and which don’t.
The second way is through Google Webmaster Tools using the Search Traffic –> Mobile Usability from the left menu. This is a good tool to use but we have found that it can state your site is NOT mobile friendly when it actually is.
The third way, which we recommend is still a Google tool, called Mobile Friendly Test, but it sits outside of the Webmaster interface and produces more accurate results.
You can read more here: 9 Things You Need to Know About Google’s Mobile-Friendly Update