Amazon.com Inc.’s and Marriott International Inc.’s mobile sites both improved on the AppDynamics/Mobile Strategies 360 Index for the week ending April 10.
On 3G, Amazon moved up five spots to No. 7 from No. 12 after a 300-kilobyte reduction in its home page weight, says Peter Kacandes, senior product marketing manager, mobile, web and synthetics, for AppDynamics. Although, the time it took for the browser to start drawing the visual elements of the mobile site home page (also called the first render time) only improved by 0.1 seconds, and the time it took for the browser to finish drawing the visual elements (visually complete time) only improved by 0.2 seconds, Kacandes says.
“This week’s 3G data shows that Amazon moved up five spots mostly through content optimization that improved its speed score by 0.8 seconds,” Kacandes says. The speed score is a composite of multiple performance metrics that determines the mobile site’s rank on the index of 30 mobile sites.
On 4G, Amazon moved up three spots to No. 8 from No. 11 the previous week. Amazon has one of the fastest start render times on the 4G index, at 2.1 seconds, however, it’s visually complete time at 10.7 seconds is above the 4G index average of 9.8 seconds. Amazon did not respond to a request for comment.
Marriott’s mobile site also displayed significant mobile performance improvements for the week ending April 10.
On the 3G index, Marriott jumped up six spots to No. 18 from No. 24 the previous week. Marriott reduced its mobile site home page weight by almost 400 kilobytes and eliminated 30 elements, such as images or links, on its home page, Kacandes says. Marriott’s visually complete time improved by 2.3 seconds and start render time improved by 1.0 seconds.
On 4G, Marriott also jumped up six spots to No. 20 from No. 26 the previous week. Marriott did not respond to a request for comment.
The exclusive AppDynamics/Mobile Strategies 360 Index tracks key mobile site metrics across a range of sites to calculate a weekly average Speed Score on both 3G and 4G mobile carrier networks. The index represents a snapshot of mobile site performance across industries, including retailers such as HSN.com, insurance companies such as NorthwesternMutual.com and restaurants such as McDonalds.com.
AppDynamics each week measures performance metrics of both 3G and 4G networks for each of the 30 sites in the index to determine each site’s Speed Score.
First render: The time, (in seconds) it takes until the web browser starts drawing the visual elements of a home page.
Visually complete: The time (in seconds) it takes until the web browser has completed drawing the visual elements of a home page.
Number of elements loaded: The number of resources loaded by a home page.
Complete load: The size of the home page when all data is loaded (in megabytes).
Using these metrics, the index calculates the Speed Score. The Speed Score is a ratio that rewards businesses for displaying more visual content on the mobile home page earlier rather than later. The earlier a mobile site home page looks complete to a consumer, the better the mobile experience for the visitor, even if a few remaining elements are displayed later. A site with a higher ratio of content displayed earlier will have a better Speed Score than a site with the same visually complete time but a longer first render time.
For example, site A may have a visually complete home page load time of three seconds, loading 90% of its content in the first second and the remaining 10% in seconds two and three. Site B may have the same three-second visually complete time, but present zero content in the first two seconds and 100% in the third second. The sites have identical visually complete times, but Site A will be perceived as much faster, and will earn a better Speed Score as a result.
The index is accompanied by a chart on MobileStrategies360.com that is refreshed weekly to illustrate how each mobile site performs as well as index averages. Click here to access the performance chart for the week ending April 10.