Don't make customers wait too long for your pages to load in their browser. Ask if your developer is aware of PageSpeed Insights (the tool above) and if they're familiar with techniques to help pages load faster. Your contract can include pages "rendering" as fast as your competitors according to WebPagetest . Or, if that's too difficult, perhaps get their commitment to a PageSpeed Insights result with a green checkmark which doesn't have any issues marked "Should Fix". (If pages don't receive a green checkmark, it's up to you and your developer to weigh the costs and benefits of correcting the issue.) More information on mobile page speed can be found in the video " Quick fixes in mobile website performance ".