Search giant Google is today implementing a major tweak to its search algorithm that will favour websites it deems to be ‘mobile-friendly’. Essentially this means that if your website is easy to view on a mobile device it may be more prominent in search results done from a smartphone. The tweak apparently doesn’t affect desktop or tablet searches.

Google took the rare step of flagging this up a couple of months ago to give developers a chance to adapt. “Starting April 21, we will be expanding our use of mobile-friendliness as a ranking signal,” said the Google blog post. “This change will affect mobile searches in all languages worldwide and will have a significant impact in our search results. Consequently, users will find it easier to get relevant, high quality search results that are optimized for their devices.”

There is even a simple tool that checks out your URL and lets you know whether it’s mobile-friendly or not (Telecoms.com is – yay). Additionally Google has already acted to make app content more prominent too.

While this might seem quite niche and technical, such is the importance of Google search to the internet economy it is causing quite a stir. Put simply, if you want to engage with smartphone users you’d better respond to this tweak. All the mainstream media are covering it today, with the appropriately geeky nickname ‘Mobilegeddon’ generally adopted and the inevitable #mobilegeddon hashtag seeing plenty of use.