In 2014, mobile sales will reach 21% of total web sales for the leading 500 retailers in mobile commerce worldwide; 23% for leading retailers in the U.S., according to data in the newly published 2015 Internet Retailer Mobile 500. But that’s practically a pittance for the seven merchants in the 2015 Mobile 500 whose 2014 mobile sales will exceed half of total web sales. These merchants are Apple Inc. (No. 2), Google Play (No. 4), Groupon Goods (No. 11), MaiMaiBao (No. 41), RueLaLa.com (No. 55), JackThreads (No. 175) and Diamond Candles (No. 220).

Mobile sales will account for 56.7% of 2014 total web sales at Apple and 80.0% at Google Play, the 2015 Mobile 500 finds. Sales at these two mobile titans are dominated by digital goods that by their very nature are generally purchased and consumed on mobile devices.

Mobile sales will account for 54% of 2014 total web sales at Groupon Goods, the retail merchandise wing of Groupon, according to the 2015 Internet Retailer Mobile 500, which ranks the leading 500 merchants in mobile commerce worldwide byprojected 2014 principal market sales on smartphones and tablets. Groupon trained its customers well: Check in every day for new, time-sensitive deals. These customers gravitated to mobile devices, especially smartphones, which they always carry and can thus use to check in with Groupon anytime during the day. 72% of consumers who visit Groupon only use mobile devices to shop Groupon; they never touch Groupon on a desktop or laptop, according to web and mobile measurement firm comScore Inc.

But what about apparel e-retailer JackThreads? Surely nothing unusually mobile about men’s apparel. Well, 52% of the web-only merchant’s 2014 total web sales will stem from mobile devices, the 2015 Mobile 500 finds.And 89% of its mobile sales currently come through its universal Apple iOS app, one designed to display well on both the Apple iPhone and iPad, though most sales come from iPhone users. Like Groupon, JackThreads trained its customers well: The e-retailer began life as a flash-sale merchant, offering time-sensitive, limited-quantity deals that made the young men who buy its clothes constantly check in on their smartphones. But today, JackThreads is primarily an “old-fashioned” apparel web merchant, not a flash-sale retailer, and all those young men have really taken to the merchant’s app.

The conversion rate for the e-retailer’s universal Apple iOS app is three times greater than the conversion rate for the merchant’s mobile web site on Apple mobile devices, says Ryan McIntyre, executive vice president of marketing at Thrillist Media Group, which owns JackThreads.

“Largely it is about the mobile shopping experience and the speed with which a transaction happens in an app versus a mobile web site,” McIntyre says. “You can securely store customer information within an app and use the full power of the mobile device rather than being limited to the full power of a mobile web browser. The smoothness of page transitions we can program into an app is tremendous, where the speed of getting from page 1 to 2 to 3 to 4 is far faster in the app.”

By comparison, mobile sales will account for 21% of total 2014 web sales at Amazon.com Inc., No. 1 in the 2015 Mobile 500. But Amazon sees the writing on the wall. Already, 29% of Amazon’s shoppers only access Amazon on a mobile device, and that number is increasing, comScore finds. Amazon recognizes that an increasing number of visits and sales will occur on mobile devices and has changed its entire mobile strategyto meet the new mobile reality in retail.

“We want a customer to be able to have 100% of their relationship with Amazon on any device they choose,” says Paul Cousineau, director of mobile shopping at Amazon.com. “Mobile is a transformative technology. As our percentage of customers adopting mobile continues to grow, mobile can no longer be a limited subset of features or products. People do not put their phone down then go find a desktop to do something. They use their phone. And we think with clever use of functions and design, it is possible to give mobile customers 100%.”

Mobile as a percent of total web sales is one of the many new data points featured in the 2015 Internet Retailer Mobile 500, which was published August 19. 53 data points were collected on each of the 500 retailers. For more information on the Mobile 500, or to order a print, digital or online database version of the annual research guide, click here.

Follow Bill Siwicki, editor of the 2015 Internet Retailer Mobile 500 and managing editor,mobile commerce, at Internet Retailer, at @IRmcommerce.

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