Like desktop content, mobile pages need to load fast. Slow loading pages rank lower in Google results. Google has a handy tool called PageSpeed Insights that will tell you how fast your pages are on both mobile and desktop browsers. There are a number of methodologies ranging from complex formulas including many different heuristics to more simplified models designed just to give you a sense of the opportunity. A professional SEO agency, filled with dedicated copywriters, optimisation experts and analysts can really make a difference for your business