Marissa Mayer: More Google Maps users on phones than PCs by June by JP Mangalindan @FortuneMagazine May 25, 2011, 10:32 PM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons From left: Marissa Mayer, Google VP of Maps and Local; Mike Arrington of TechCrunch. Photo: JP Mangalindan/Fortune FORTUNE — Despite a recent management reorganization at Google GOOG , Marissa Mayer, now vice president of Maps and Local, says it’s business of usual, describing the company atmosphere as “optimistic.” At TechCrunch Disrupt in New York City, Mayer focused on the progress of her division, and while the basic theme of her discussion was something we’ve seen coming for a while now — the tide is shifting from desktop to mobile — she gave the audience the numbers to back it up. Users of Google Maps, which just recently surpassed 200 million mobile device installations, now use the service 40% of the time through their smartphones, a percentage that climbs on the weekends, presumably when people are trying to find the apple orchard, national park or backyard BBQ they are heading out to visit. And come this June, Mayer said, the ratio of desktop to mobile usage will flip: the majority of users will use Maps most of the time on their phones instead. Mayer welcomes the change. “Maps on the phone that know. . .where you are and where you’re going is a killer app,” she said. Mayer wants the services she’s in charge of to go above and beyond simply helping people find their way. She wants an added layer of contextual discovery. Not just better local business recommendations, but say, factoids about establishments like what other customers at a restaurant recently ordered, liked, or disliked. To do that, Mayer wants more users to check-in with say, Latitude, Google’s relatively new social check-in service, and ultimately enrich the amount of user data at Google’s disposal for further product iteration because the richer the user data, the more customized and personalized their services can get.