Google has been giving webmasters some pretty heavy hints that mobile-friendliness was important to the search engine, and today the company made it official. Mobile-friendliness and indexed apps are officially ranking factors in search results.
The motive behind the addition to the search engine algorithms is fairly obvious. People are using mobile devices more and more to search the web, and mobile-focused ranking factors such as these are the best way to ensure quality results no matter what device you come from.
The mobile algorithm update won’t take effect until April 21, so you have time to make any necessary changes you may have been procrastinating on until now. Google also says the update will affect all mobile searches in any language around the world.
If you are concerned your site may not be up to Google’s mobile standards, they offer a mobile-friendly test. Google also suggests examining mobile usability issues by reviewing the Mobile Usability Report in Google Webmaster Tools.
In the meantime, Google will begin considering information from indexed apps as a ranking factor for signed-in users with the app installed on their phone. This way, content from indexed apps on your phone have the potential to rank higher in the search results you see. As a side-effect however, app developers will have to establish a relationship between their sites and app deep links.