Starbucks on Wednesday unveiled a new mobile payment system that will be available in all U.S. stores for BlackBerry and Apple iOS users.

The option is available via the Starbucks Card Mobile App, which can be downloaded from the App Store or the Starbucks Web site. Users then load money onto the app with any major credit card, hold their phones in front of a scanner on the countertop, and scan the on-screen barcode to purchase.

The Starbucks Card Mobile App has been available since last year, and initially let all users check their Starbucks card balance, reload the card, and view transactions. Starbucks also kicked off a mobile payment test in certain Seattle, Northern California, New York, and Target store locations; it has now expanded that feature nationwide.

Mobile payment is available on iPhone and iPod touch devices running iOS 4.0 or higher. BlackBerry users can also access it by texting "GO" to 70845 or visiting the Starbucks mobile site. Supported BlackBerry devices include the BlackBerry 8800 series, BlackBerry Bold, Curve, Storm, Storm2, and Tour.

"Today, one in five Starbucks transactions is made using a Starbucks Card and mobile payment will extend the way our customers experience and use their Starbucks Card," Brady Brewer, vice president of Starbucks Card and Brand Loyalty, said in a statement.

Starbucks said customers loaded $1.5 billion onto Starbucks Cards in 2010, a 21 percent jump over 2009. That was driven, in part, by the company's rewards program, which provides benefits to customers who pay with Starbucks Cards.

The announcement comes several months after Starbucks partnered with Yahoo to launch the Starbucks Digital Network, a package of Web content available only in Starbucks stores over its free Wi-Fi networks.