AppDynamics is now the exclusive provider of performance data for the Internet Retailer Mobile 500, a comprehensive annual review of the world’s top 500 companies based on revenue generated through their mobile application.

The 2016 edition of this highly regarded reference guide was published this month online and in print. In addition to industry trends and analysis, the database version of this guide provides a summary of key data about each of the 500 retailers, including financial, operational, and corporate summaries, and a snapshot of mobile site performance as measured by AppDynamics.

“Smartphone performance is critical to the success of mobile retailers, and something retailers are very interested in,” said Katie Evans, Editor, Mobile at Internet Retailer. “We chose AppDynamics as our performance monitoring partner so our readers can have a vivid picture of each site’s performance — not just raw page-load numbers, but a real sense of what the experience is like for end users, which the AppDynamics Speed Score provides. We’re confident that AppDynamics’ mobile measurement technology and methodology give our readers metrics that are accurate and useful, so they can see how others are doing and gauge their own mobile performance.”

AppDynamics’ analysis of the data shows a wide divergence in mobile retail site performance, with the fastest sites earning speed scores of 1.8 and 1.1 seconds over 3G and 4G, respectively, and the slowest crawling in at 43.5 seconds over 3G and 34 seconds over 4G.

“Even though retailers have been addressing the mobile channel for several years now, many if not most clearly still have a long way to go to deliver the kind of experience consumers expect,” said Kalyan Ramanathan, VP of Marketing for AppDynamics. “The research is pretty conclusive that consumer expectations of mobile are not that different than desktop — they really want the site to load in three to five seconds. In our Mobile 500 measurements, only 76 sites achieved Speed Scores in the ‘fives’ on 3G. On 4G, over half — 309 — achieved a Speed Score in the five’s. Of course, this is just one metric that indicates relative speed, and there are trade-offs. But retailers need to stay focused on squeezing as much speed as they can out of their mobile sites. There’s a lot of room for improvement.”

Poor performance costs retailers real money. A one-second delay costs Amazon $1.6 billion in sales according to Fast Company. While this is perhaps the most extreme example, every retailer should know that slow mobile performance will rob their bottom line; 74% of users say they will leave a website if it does not load in less than five seconds. And the importance of the mobile channel for retail keeps growing. Last holiday season, according to IBM’s annual holiday benchmark report, mobile sales grew by double digits, and mobile accounted for more than half of all online traffic on both Thanksgiving and Christmas Days. Mobile, including smartphones and tablets, delivered nearly 28 percent of sales on Black Friday, and 22 percent of sales on Cyber Monday.

AppDynamics Mobile Measurement Methodology: AppDynamics measured the 500 sites from locations in North America, Europe and Asia using its Browser Synthetic Monitoring technology. Measurements were made over a week-long period using the Chrome mobile browser, and included time-to-first-render (in seconds), visually complete time (in seconds), number of elements loaded, and total page weight (in megabytes). The speed score is then calculated from the detailed performance data.

“The Speed Score is a more accurate reflection of the actual user experience than the raw page metrics provide,” explained Peter Kacandes, Senior Product Marketing Manager, Mobile Application Management and Monitoring, for AppDynamics. “For example, site A and site B may both be “visually complete” in six seconds, but site A may render 80 percent of its content in the first three seconds, and site B only renders 10 percent of its content in that initial period. They’re both done in six seconds, but the user will perceive site A as much faster, and so it’s going to earn a better speed score.”

Analysis of the 2016 Mobile 500 data shows there is more than one way to achieve a high-performing site. Overall page weight is an obvious and significant factor, but the total number of elements and the order they are loaded are also important optimization targets.

“This data shows that, on average, each megabyte of page weight takes almost 9.9 seconds to load over 3G, and 6.8 seconds at 4G speeds,” said Ian Withrow, group product manager at AppDynamics. “So, if your goal is to load in less than five seconds, you should aim for a page weight of half-a-megabyte. But the number of objects also make a big difference. A page with one 1,000k object doesn’t load the same as a page with ten 100k objects, and it’s not necessarily faster. If you’ve got multiple objects, as most sites do, the order they load also impacts perceived speed, which impacts the Speed Score.”

AppDynamics offers both Browser Synthetic Monitoring and Real-User Monitoring for mobile applications and browsers (mobile and desktop), which provides complete, end-to-end visibility from device to backend infrastructure, for proactive application performance management, optimization, and analytics.