SAN FRANCISCO (AP) — eBay shoppers are using their cell phones to make purchases more and more frequently: The company said Wednesday that eBay users completed more than $600 million worth of transactions on cell phones last year, and that its application for Apple’s popular iPhone has been downloaded nearly 7 million times.

During a conference call with analysts Wednesday regarding the auction and e-commerce site operator’s second-quarter results, CEO John Donahoe responded to a question about whether mobile is becoming an important part of eBay’s business.

QUESTION: Are mobile transactions becoming a meaningful contributor to your revenue?

ANSWER: “Mobile, absolutely, I think, is in the phase of an inflection point and there’s no doubt that the iPhone and smartphones in general have just illustrated to consumers all over the world the power of what a mobile device can provide.”

“We have been quite fortunate in that both eBay and PayPal lend themselves to the mobile format well. The engaging nature of eBay auctions is really something that can be brought to a mobile device. And our best sense is our mobile commerce offering, at $600 million (in gross merchandise volume in 2009), could be half the volume in the mobile goods market thus far.”

EBay’s fourth-quarter earnings rose as its PayPal payments business grew and holiday shoppers gravitated to its online auctions and “Buy It Now” offerings. The company also logged a large gain from the November sale of its Skype telecommunications business.

The fourth-quarter results, combined with eBay’s forecast for a first quarter in line with or better than what analysts have expected, helped its shares rise more than 8 percent in extended trading.