Content is of course crucial to any mobile commerce experience. An m-commerce site has to have text, images and other elements to present merchandise to shoppers. But if an element or object—a piece of content on a page—creates an error during a download that can have a negative impact on site performance. A content error, for example, could stem from a non-optimized image refusing to download.

Several sites on the Keynote Mobile Commerce Performance Index, provided exclusively to Internet Retailer, did very well last week when it came to downloading content in a manner that positively affected mobile site performance.

“Keynote captures data not only related to overall page reliability, but also to reliability of each piece of content on a page. We discovered that six of the seven sites rated highest in reliability last week also had zero content errors, while the two lowest ranked sites in reliability had the highest content error rate,” says Herman Ng, mobile performance evangelist at Keynote Systems Inc. “The lowest content error rate was zero percent, while the highest was 16.76% and the median was 0.06%. We also observed that content error rates vary across measurements on different carriers, which implies that the wireless connection itself is a variable in terms of whether a page element can be successfully downloaded by a mobile device. So while resolving all content errors might not necessarily move any one site to the top of the index, having a high number of content errors will definitely affect a site’s ranking and ultimately the end-user experience.”

Last week, the top five performers on the Keynote Mobile Commerce Performance Index were, in order: StrandBooks.com, Barnes & Noble, Walmart.com, Dell and Victoria’s Secret. They ranged from StrandBooks.com having a score of 881 out of 1,000, its m-commerce site home page downloading on average in 2.98 seconds and doing so successfully 98.42% of the time, to Victoria’s Secret having a score of 694, with a download time of 5.94 seconds and a success rate of 99.12%.

The average download time for all 15 retailers in the index was 5.51 seconds with a success rate of 98.20% for a score of 581. Click here then click on Keynote Mobile Commerce Performance Index to see the complete results of all 15 retailers.

Mobile and web performance management firm Keynote Systems measures 15 representative m-commerce sites exclusively for Internet Retailer. The sites include merchants in various categories and channels, and of various sizes, ranging from such giants as Sears Holdings Corp. and Foot Locker Inc. to midsized retailers like Sunglass Hut and K&L Wine Merchants. Keynote repeatedly tests the sites in the index Monday through Friday from 8 a.m. through midnight Eastern time, emulating three different smartphones on three different wireless networks: Apple Inc.’s iPhone on AT&T, the BlackBerry Curve on Sprint and the Droid (which uses Google Inc.’s Android operating system) on Verizon.

Keynote combines a site’s load time and success rate, equally weighted, into a single score. Given both performance and availability are important, the score reflects the overall quality of the home page; a higher score indicates better performance. Scores also reflect how close sites are to each other in overall quality. The index average score is the midpoint among all the sites’ scores.