The Secrets Hidden in Our Google Location Data: Decrypted Podcast.

Indeed, Schindler stressed that Google would generate personalized Maps recommendations in "privacy-sensitive, opt-in ways."

The company is betting that adding more data about places and businesses to Maps will lead people to spend more time on the service. As users expect more from Maps, Google has extra space to introduce more ads.

“We want to be able to highlight things that are around you and surface them nearby to you in a way that’s not disrupting your experience,’’ said Rajas Moonka, director of product management for Google Maps. Because so much of what users are looking for in Google Maps is commercial in nature, ads can be a helpful addition to the experience, he said.

The company has tested ads in Maps for years, and it owns Waze, a navigation app that runs ads and has been downloaded more than 100 million times. But Google has taken it slow. "We’ve been pretty careful about not being very aggressive about how we present those to users because we don’t want users to feel like we’re overloading the experience," Moonka said.

Moonka, a Google veteran, was tapped to run Maps advertising about two years ago. He sees the offering as a more effective alternative for small businesses that often use email marketing to find potential customers.

“It’s very un-targeted, and that’s the most effective channel that most people have to convey information to you,” he said. “There is an opportunity here to do this in a way that’s really tailored to the user in the long run.”

Last summer, voice-based directions from the Maps app started mentioning well-known brand names from companies that are already big buyers of Google’s search ads. Instead of "turn right on Schindler Avenue," the app sometimes says "turn right at the Starbucks." Or the Dunkin Donuts or the local paint shop. Google said these are not ads, adding that fast food chains, banks and other businesses are helpful landmarks to orient Maps users.

For the last two years, Google has also tested "promoted pins," waypoints emblazoned with an advertiser’s brand that show up on the map regardless of whether or not the user searched for that business. McDonald’s Corp., Dunkin’ Brands Group Inc. and Michael Kors Holdings Ltd. are among adopters.

Small businesses can also get access to pins as part of a package of ads Google places on different parts of its digital empire depending on where it thinks they’ll be most effective.