The June 2014 cover story of Internet Retailer magazine will reveal Internet Retailer-exclusive research from performance firm Keynote that shows retail responsive design sites load at a snail’s pace on smartphones. But some pioneering vendors are showing ways to vastly improve responsive page load times.

Retail responsive design sites load quickly on desktops and tablets, but smartphones are an entirely different story: The average home page load time on smartphones via a blend of 3G and 4G wireless speeds for 12 retail responsive design sites throughout February 2014 approached 20 seconds, according to an Internet Retailer-exclusive study conducted by mobile and web performance testing, monitoring and analytics firm Keynote.

Keynote recommends smartphone page load times between 2 and 6 seconds, depending on the connection speed. Responsive design as it has been employed to date in retail creates a wholly unacceptable experience on smartphones, says Ken Harker, a senior performance analyst at Keynote. However, some vendors, knowing the undeniable allure of responsive design where a retailer can build one site (serving all devices) instead of three (desktop, tablet, smartphone), have debuted technologies that speed responsive design page loads.

Yottaa, for example, is a vendor that specializes, quite specifically, in optimizing web site page load speed and customer conversion. Yottaa significantly improved performance for its e-retailer client The Yankee Retail Company LLC’s hybrid responsive design site, Yottaa optimization reduced 4G smartphone response time 56%, from 13.3 seconds to 5.9 seconds, and Wi-Fi smartphone response time 61%, from 8.4 seconds to 3.2 seconds, says Justin Potts, CEO of Yankee Retail. What’s more, Yottaa optimization reduced 4G smartphone “time to start render” 35%, from 3.11 seconds to 2.04 seconds, and Wi-Fi smartphone “time to start render” 32%, from 1.57 seconds to 1.06 seconds, Potts says.

Consumers can begin viewing and sometimes even interacting with a web site at the point of “time to start render,” which is significant as that greatly enhances a consumer’s perception of page load speed.

After Yottaa’s optimization of the responsive design, page views per visit on smartphones jumped 20.9%, average visit duration on smartphones rose 21.3%, and smartphone conversion rate increased 5.0%, Potts says. (The retailer also saw 30.6% and 46.4% increases in conversion on desktops and tablets, respectively.)


Yotta CEO Coach Wei says the vendor, which delivers its services via web hosting at 30 data centers around the world, takes a variety of steps to improve performance on responsive design sites, including:

  • Breaking HTML pages into small fragments and first shipping only the fragments required for what is immediately displayed, later delivering other fragments as needed.
  • “Sequencing” (prioritizing) the order of different elements on a page so the important elements show first.
  • Resizing, compressing and sequencing images based on the profile of the device requesting a page, enabling both the high-resolution experience on tablets and PCs while delivering fast performance on smartphones, Wei says.

“Customers don’t need to recode their site to use Yottaa,” Wei says. “It applies optimizations when traffic is being routed in real time.”

Yotta charges retailers a monthly fee, typically a few thousand dollars, though on the high end can reach $20,000, depending on the size of a web site and monthly traffic. Potts says Yankee Retail has more than achieved return on investment.

On another front, e-commerce and m-commerce platform provider UniteU Technologies Inc. declares responsive design site performance problems “a myth.” It launched a hybrid responsive design site for e-retailer City Sports in 2013, and City Sports today reports smartphone load times of 6.02 seconds on 3G, 2.12 seconds on 4G LTE and 0.86 seconds on cable modem. City Sports also reports a big 30% increase in the conversion rate on smartphones since going responsive with UniteU.


So why is responsive design not a joy-clamp for smartphone shoppers on City Sports? Because UniteU has a secret: Where most responsive design sites have only one code base, UniteU responsive design sites have two—one for desktop/tablet and another for smartphone.

UniteU’s techniques to speed responsive sites on smartphones include:

  • Aggregating JavaScript files, collapsing and compressing five files, for example, into one, which reduces server requests from five to one.
  • Minifying files. Minifying involves removing all unnecessary characters from source code without affecting functionality; this reduces the size of a file and thus shaves off time from the total page load time.
  • Using sprites, a web programming technique that enables multiple images to be saved as one, thus reducing the number of web server calls required and shaving time off of page loads.
  • Splitting the smartphone version of the site from the desktop/tablet version, thus sending to a smartphone only what is needed to render the site for that device.

UniteU CEO Soumen Das says responsive design as  an add-on to its core e-commerce offering  costs about $15,000 to build and $225 a month to operate. UniteU e-commerce sites, with mobile responsive included, cost between $50,000 and $300,000 to build and $1,500 to $30,000 a month, depending on size.

The full report on the 12 retail responsive design sites tested by Keynote will appear exclusively in the cover story of the June 2014 issue of Internet Retailer magazine. The report includes data on each of the 12 sites, analysis by experts in the performance field, and ways to improve the performance of retail responsive design sites.