Starbucks is adding a new flavor to its mobile payments strategy: BlackBerry. The Seattle-based coffee chain is launching a free BlackBerry app that lets people use the devices to buy coffee in stores via barcode scan. Starbucks introduced the same kind of app for iPhone and iPod touch a year ago.

The BlackBerry app lets people check their Starbucks Card balance, add money to their account with a credit card, and make purchases at Starbucks. At checkout, the app generates a barcode on the BlackBerry screen, which is then swiped over a scanner.

Right now the mobile payment feature only works at a limited number of locations: 16 Starbucks stores in Seattle and Silicon Valley, and about 1,000 Starbucks inside Target stores. But Starbucks "is looking to expand the test," said Chuck Davidson, category manager, innovation for the Starbucks Card unit.

Davidson declined to share data on how many people are using the iPhone and iPod touch apps or how much in the way of sales they've produced. But he said Starbucks is "really pleased with the performance of the payment trial," and said the mobile apps are faster than paying with cash or a credit card.

Here's a map of the Starbucks stores in Seattle that accept mobile payment.

The mobile apps are just part of Starbucks digital strategy.

The company recently introduced free, unlimited Wi-Fi in company-owned stores in the U.S. and Canada, and it's preparing to launch a digital network in stores this fall. The digital network will feature various content, including news, iTunes, restaurant reviews, fitness info, kids' games, and charity donations.

See my earlier story: Big digital ambitions may be brewing at Starbucks

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