Say you need a latté. You might pull out your phone, open the Yelp app and search for a nearby cafe. If instead you want to buy an espresso machine, you will most likely tap Amazon.com.

Either way, Google lost a customer.

Google remains the undisputed king of search, with about two-thirds of the market. But the nature of search is changing, especially as more people search for what they want to buy, eat or learn on their mobile devices. This has put the $22 billion search industry, perhaps the most lucrative and influential of online businesses, at its most significant crossroad since its invention.

No longer do consumers want to search the Web like the index of a book — finding links at which a particular keyword appears. They expect new kinds of customized search, like that on topical sites such as Yelp, TripAdvisor or Amazon, which are chipping away at Google’s hold. Google and its competitors are trying to develop the knowledge and comprehension to answer specific queries, not just point users in the right direction.

“What people want is, ‘You ask a very simple question and you get a very simple answer,’ ” said Oren Etzioni, a professor at the University of Washington who has co-founded companies for shopping and flight search. “We don’t want the 10 blue links on that small screen. We want to know the closest sushi place, make a reservation and be on our way.”