Think back to the last time you paid a visit to a website you’d previously visited on a desktop from your smartphone. Your experience interacting with the site in question via a different device almost certainly fell into one of three categories: awful, ok or awesome. Now ask yourself, what exactly was responsible for your rating? If you’re anything like the other 271 million mobile device owners here in the U.S. (91% of whom keep their phones within arms reach 24 hours a day, seven days a week); your critical assessment probably depends on how good of a job that website did of serving itself to your smartphone.