- Brian Morrissey

Google is building out its mobile ad arsenal by expanding its new click-to-call ad options.
 
The company is providing the smartphone ad option to national advertisers seeeking to give mobile users the ability to tap numbers in ads to connect with businesses. The click-to-call ads had previously been limited to firms with local numbers.
 
The click-to-call options are available for more sophisticated handsets using Google's Android operating system, as well as Apple iPhones and Palm Pres.
 
In the program's first month, Google found that ads with click-to-call options got 5-30 percent increases in response rates.

Surojit Chatterjee, product manager for local mobile ads at Google, attributes this to the fact that users tend to more often respond to promos that contain specific information, such as addresses. "We think if you put more information in the ad, people will begin to trust the ad a little more," he said.
 
Razorfish has used the click-to-call ads for clients like Carnival Cruises. Clients see an 8-12 percent increase in response when mobile ads include information specific to the user on the go, according to Samantha Hartsfield, search account manager. "We're trying to figure out how people are using mobile," she said. "It allows us to use search as research."
 
Other companies offer click-to-call ads, but they typically charge much higher prices per call compared to a click on a search ad. Google has opted to price a call equal to a click.
 
"The volume isn't there, but it's steadily growing," Hartsfield said.
 
Google is attacking the emerging mobile ad space from several directions. On the hardware and operating side, it has developed Android and the Nexus One phone. It also bought mobile ad network AdMob for $750 million last November.