Location Labs sells a service that notifies parents where their children are. The company has focused on being highly transparent, with regular reminders about what information it uses, and keeps that service limited to the users on a subscriber's own family plan. "Transparency and control are how you get by the creepiness factor," Grossman said.

The conference, which continues through Thursday in Burlingame, California, finds a well established industry playing in a new world of mobile applications.

The LBS (location-based services) industry that grew up around navigation and other applications of GPS (Global Positioning System) is now integral to the mobile revolution and is powering popular services and valuable advertising, representatives of software and services companies said on two panel discussions. Technologies that once were intended primarily for consumers finding out or disclosing where they were have become the foundations of applications built on top of those capabilities, they said.

For example, startup FourSquare built its all-mobile application around consumers' ability to "check in" to their current applications, but found last year that consuming location and other information was becoming the bigger part of its business, according to Holger Luedorf, vice president and head of business development. All the data that the app collects can help consumers follow their friends' recommendations and find out what's popular nearby, and businesses have tapped into Foursquare for locally targeted advertising, Luedorf said.

Likewise, online discount service Groupon is now working with Nokia to layer the locations of businesses with Groupon deals on top of the maps on Nokia's phones. That service is coming later this year, said Andreas Lieber, director of mobile partnerships at Groupon.