Ever wonder what the little lightning bolt icon means when you do a Google search on your mobile device? These are AMP or "Accelerated Mobile Pages". As internet use continues to shift toward mobile use, it becomes more and more important to address these users. Its now estimated that more than half of web traffic is mobile. Additionally, Google has been increasing the importance of pagespeed, or page load time, in its search result ranking algorithm.
You can see for yourself what % of your site's traffic is mobile in your Google Analytics reports.