Starting from May, websites that are not optimized for mobile devices will begin to suffer penalties on Google rankings. The announcement, coming from Google itself, remember the importance of having a mobile-friendly website, developed with a responsive layout, which allows an optimal viewing on tablets and smartphones.
Today, April 21st 2015, Google has made some major changes to its search algorithm. The change is so important to take the nickname Mobilegeddon. It was announced in late February and substantially affect the positioning of mobile-friendly websites, properly optimized for mobile devices (smartphones and tablets).