Starbucks is letting consumers swipe their smartphones to buy a latte. The company is launching a mobile payment system, and marketers might find this tool familiarizes consumers with the rising world of mobile commerce.

Starbucks announced today that customers at all U.S. store locations can pay for in-store purchases with their smartphones. The system requires consumers to download a free Starbucks Card Mobile app (currently available for select BlackBerry, iPhone and iPod devices). Users pay by holding their smartphones to an in-store scanner.

"With mobile payment, the Starbucks Card platform further elevates the customer experience by delivering convenience, rewarding loyalty and continuing to build an emotional connection with our customers," said Brady Brewer, vice president of the Starbucks card and brand loyalty.

In-store mobile payments with this popular coffee brand could help consumers get more comfortable making purchases with their phones, giving mobile commerce another push toward the mainstream.

Brafton reported that shopping via mobile devices was increasingly common during the 2010 holiday season, and mobile shoppers are expected to spend $119 billion by 2015. Marketers may want to plan mobile campaigns accordingly.