Updated

Google's collection of location information from millions of mobile devices and personal computers is "extremely valuable" to the company's future business, according to an email written by a Google product manager last year.

That email and others, which are part of a public filing in a lawsuit against Google last year, shed new light on the company's thinking about the need to gather location-related data.

Such information is essential for a growing number of mobile applications and websites to function properly, the emails indicate. It is also useful for companies such as Google — whose Android software powers millions of phones—that want to offer consumers advertisements that are tailored to their locations, a new frontier for online ads.

The disclosure of the internal emails follows a series of other revelations about location data gathered by Google and Apple. The revelations prompted the U.S. Senate Judiciary Committee to schedule a hearing on May 10 to discuss the companies' practices.

Google, with users' permission, collects information about wireless networks surrounding mobile devices powered by Google's Android operating system. It also gets information about the location of wireless networks near personal computers if the PCs' owners are using Google's Chrome Web browser or versions of some other browsers.

Tech companies are using such information to build databases of millions of wireless networks, or Wi-Fi "access points," which help determine the approximate location of phones and computers attached to those networks. Using Wi-Fi is more accurate than satellite-based signals known as GPS, Google has said.

"I cannot stress enough how important Google's Wi-Fi location database is to our Android and mobile-product strategy," wrote Steve Lee, the Google product manager, in an email that emerged in a suit filed against Google by Skyhook Wireless Inc. in a Massachusetts court. The message was a response to an emailed question last May by Larry Page, who is now Google's chief executive.

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