The coffee giant also plans to add mobile payment capabilities to Starbucks shops in 1,000 Safeway stores, bringing the number of places where mobile payments work to nearly 9,000 in the U.S. That number includes 6,800 company-owned Starbucks and another 1,000 locations inside of Target stores, said Chuck Davidson, category manager for innovation on the Starbucks card.

Davidson said that Starbucks has done so well with its mobile payment app -- a reader in the store scans barcodes displayed on smartphone screens -- that it doesn't make sense to wait for the arrival of Near Field Communication (NFC) mobile payment technology.

"Having NFC readers [inside stores] is not the issue; it's [having enough] NFC [chips] in the phones, which we believe is two-and-a-half to three years out," Davidson said in a conference call with reporters.

Davidson said Starbucks saw 3 million mobile payment transactions in just nine weeks when the iPhone and BlackBerry apps were launched earlier this year, though he didn't provide more detailed information. "That's a big number in a short period of time, which we achieved with no complaints and no training issues," he added.

Starbucks did plenty of preparation for the mobile payment system, building on its successful Starbucks card, he said. The card originally began as a gift card and now allows users to pay by phone quickly at a bar code scanner. It can also be used to reload dollars to the card from any major credit card and to check Starbucks Rewards for winning a free drink and finding nearby Starbucks locations.