Recent reports by Forbes magazine and technology news source Ars Technica say that Internet Explorer from Microsoft Corp. is regaining the lead as the world’s most popular browser. I’m skeptical. I don’t know anyone who uses IE by choice—except maybe my grandparents.

So, I polled a roomful of my twenty-something peers who agreed that when it’s up to us, it’s Google Chrome. If we were a Mac crowd, I’d expect the same for Apple Safari. (IPhones and iPads run Safari by default, as do all Macintosh devices.)  Only when forced to—for example, when IE is already installed on a company computer—do my friends and I use the Microsoft browser.

Then I looked for some evidence to counter the claims of Internet Explorer’s popularity and found what I wanted: The graph below, compiled by e-mail ad platform provider LiveIntent.

LiveIntent places advertising in millions of e-mail newsletters and alerts worldwide each day on behalf of more than 100 publishers. It uses third-party databases to obtain demographic information about who opens the messages for advertisers who request audience segmentation.

The data show that the younger set indeed prefers Google’s Chrome and Apple’s Safari browsers to Internet Explorer. Moreover, the majority of those aged 21 to 35 in the LiveIntent pool open e-mails with the iPhone. Although iPhone users account for less than 25% of the total e-mail opens, the great popularity of the Apple device in that age range is apparent. Many consumers also open e-mails on Android mobile devices—this is clearly a mobile generation. Additionally, younger consumers frequently use Firefox while on PCs.

For retailers, this data demands attention for two reasons. One, if you’re not optimizing your e-commerce site for mobile browsing on Apple and Android devices you risk losing out on selling to younger consumers who tend to be avid buyers of fashion, electronics and home décor. Consumers quickly ignore sites that don’t render well on mobile devices. With more and more of them using smartphones to shop, the losses will only increase.

Secondly, looking ahead, retailers might consider giving less weight to Internet Explorer in testing how well their sites render on a PC.  In an extreme case, one online startup with limited resources, portfolio-hosting service 4ormat, decided to completely drop IE support for their web pages and saved $100,000, TechCrunch reported recently. For this small web site operator, paying attention to the specific demographic of its clients resulted in significant savings.

For any retailer, it’s all about knowing its customers and figuring out the best way to allocate limited resources. For the time being, many consumers still use IE, as even 4ormat realizes.

“Choosing to not support certain browsers or spending more time on other browsers is directly related to your resources and audience. Any retailer would want good support for IE7 and above, just because so many people are locked into IE in corporate environments and make purchases while at work,” 4ormat co-founder Tyler Rooney told me in an e-mail. “That said, I feel like many new retailers might see a better use of resources by degrading features on IE7/8 and spending more time on fully featured sites for mobile browsers.” He went on to cite recent reports of iPad shoppers purchasing not only more frequently, but also spending more than desktop shoppers.

The data speak, and retailers would be well advised to pay attention to the browsing trends of the increasingly mobile younger generation of shoppers.

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