SAN FRANCISCO: Mobile devices such as smartphones and tablets will vastly expand the number of companies who advertise online and will allow Internet companies to reap more revenue than they have from customers on PCs, Google Inc Chief Business Officer Nikesh Arora said on Wednesday.

Small, local businesses will represent the largest influx of new marketers as they discover the benefits of reaching on-the-go consumers on their mobile devices, Arora said, speaking at the Morgan Stanley Technology, Media and Telecom Conference in San Francisco.

"The desktop world took the world of advertisers from tens of thousands to a few million," Arora said. "I think as we go forward, that a few million becomes tens of millions as mobility becomes more relevant."

Arora also said that monetization on mobile will eventually "become a multiple" of the current rate of monetization on desktop PCs.

Google, the world's No.1 Internet search engine, generates the vast majority of its revenue from advertising. But its ad rates, like those of other Internet companies including Yahoo, have been under pressure as more consumers access its online services on small-screened mobile devices, where advertising rates are lower than on PCs.