Google's head of mobile services is looking for your trust.

Sharing your current location with a data-hoarder like Google might seem unattractive to some people, but greater trust could open the way to a whole range of location-based services, said Deep Nishar, Google's mobile product management director.

"Technology is available to tie location with what kind of searches you provide and what kind of results you provide," Nishar said in an interview Thursday. "However, that depends on what the mobile operator is willing to provide to a service provider like Google and also the privacy laws of the country."

The approximate location of a cell phone user can be determined using the cell phone towers to which the phone connects, and some advanced handsets include GPS (global positioning system) receivers capable of accuracy down to a few meters.

Armed with this information, results from searches on mobile phones could be tailored to the location of the user at that time. For example, a search for a bookstore or restaurant would count the closest shops as the most relevant, while a search for a movie would provide a list of starting times at local cinemas. However, in many countries local laws or privacy concerns stop carriers from sharing location data with companies like Google.

For that to change, companies like Google and cell phone carriers will have to gain the acceptance of users, said Nishar.

"It's more a matter of trust and really understanding," he said. "People don't think twice about giving their credit information online but they might think twice about saying 'Oh, I'm driving here and I don't want that to be known.'"

A possible solution would be to offer users a choice over when such information is shared.

"If users could say 'OK, right now I am willing to let people know where I am but another time I want to turn that ability off' then that might also provide a better opportunity for widespread use of that service," said Nishar.

Google has been aggressively expanding its mobile footprint in the last few months.

Its most recent deal was signed Thursday with Japanese carrier KDDI and will see the Google search box appear on about 20 million cell phone screens in the country.

Since the beginning of this year similar deals have been struck with other carriers including the world's largest mobile operator, Vodafone Group, and device makers including Motorola, Sony Ericsson Mobile Communications and BenQ Mobile GmbH & Co. OHG.

There's a good reason for this expansion: there are about twice as many cell phones in the world as computers, and the cell phone market is growing faster, said Nishar. But for Google, a more relevant number is people using wireless Internet services.

That may still be small in many countries, but Nishar believes that as better technology, such as 3G, spreads, more people will search from phones while in transit.

"It's not a cultural barrier," he said. "Information is pervasive and the thirst for knowledge is common around the world."