Why Google is pulling the plug on Frommer’s

FORTUNE — Spotting a tourist used to be easy. Just look for someone toting around a travel guide. Today, vacationers are organizing their trips entirely online. All they need to carry with them is a smartphone to occasionally look up tourist attractions and navigate around town.

Travel guide publishers are in upheaval amid this new reality. Sales of guidebooks are down sharply as people instead turn to sites like TripAdvisor for hotel and restaurant reviews. The industry’s decline was hammered home recently with two big developments.

The latest came Thursday with word that Google (GOOG) planned to kill the print edition of Frommer’s, the travel guide giant it acquired last year. Google declined to comment, although Skift, a travel news site, reported that Google’s editors had already broken the news to authors of some upcoming titles. Frommer’s has long been a Bible for globetrotters, and its extinction in print, at least, would be a big loss for the travel guide industry. Google could continue to publish digital books under the Frommer’s name and keep Frommer’s website alive, however.

The second development, the BBC’s sale of Lonely Planet, happened earlier this month. The British broadcaster disclosed plans to sell the guide-book publisher for $78 million, far less than the nearly $200 million it had originally paid. The buyer, NC2 Media, a Nashville-based media company controlled by reclusive billionaire Brad Kelley, promises to continue publishing travel guides. But the huge loss the BBC took on the sale highlights the difficulty travel guide businesses face in the digital age. “If you go back 15 or 20 years, a guidebook was the only source of information for a traveler to go on,” said Stephen Palmer, managing director for Lonely Planet. “Now people are using six to eight different sources of information to plan that trip. We believe the guidebook still has a role in that mix.”

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The decline in guidebook sales started with the recession, which decimated leisure travel. The influx of mobile devices compounded the problem. Bookstores like Borders, a big source of travel guide sales, shut down en masse. Free online travel information became more readily available, further eliminating the need to pay $30 for a guidebook.

Major travel booking engines like Expedia (EXPE), Orbitz (OWW) and TripAdvisor (TRIP) all make hotel reviews from users available to people deciding where to stay, for example. AirBnB and VRBO.com, which focus on private vacation rentals, have similar critiques. You’d have to go pretty far off the beaten path to find a hotel, restaurant, or bar that hasn’t been praised or panned somewhere online. The question is whether anonymous critics are as trustworthy as professional travel writers.

Travel guides must also compete against free open source guides, which are written by volunteers. Wikitravel and Wikivoyage, a branch of Wikipedia, offer free online travel tips for cities and countries around the world. Their prose tends to be utilitarian compared with some of the professionally written guides. But they generally give a decent overview, with the usual details about hotels, tourist sites, and how to get around.

Google’s brief history with travel guides started when it acquired Frommer’s along with the Unofficial Guide series from John Wiley & Sons for $22 million. It wasn’t Google first foray into print, however. A year earlier, it had bought Zagat Survey, best known for its restaurant ratings. Google planned to incorporate both Frommer’s and Zagat reviews into its online products. The rise of Yelp (YELP) and TripAdvisor had showed that reviews could be valuable.

What Google would do with Frommer’s print business was always a question, however. The match between the online Goliath and an older school publisher seemed odd. A number of Frommer’s titles scheduled for release in February and earlier this month are now overdue. The most recent titles published focusing on Napa and Sonoma in California’s Wine Country along with Banff and the Canadian Rockies, may be the last to be printed with Frommer’s name.

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Palmer, from Lonely Planet, said that the demise of Frommer’s print guides would be an opportunity for his business to gain market share. But he’s still waiting to see how the situation plays out. Lonely Planet sells around 5 million guidebooks annually, Palmer said. But sales are lower than they were before the recession.

U.S. guidebook sales are down 10% to 20% since 2008, he said. Recently, sales have stabilized, providing a glimmer of hope. To reach a bigger audience, Lonely Planet has started a new series of books, Discover, that are for more mainstream travelers who must make due with shorter vacations. “I don’t think anyone is pretending that sales of travel guides aren’t down,” Palmer said. “But they aren’t off a cliff. What we’re seeing now is a level of stability.”

Like many travel guide publishers, Lonely Planet is investing in its online business. And like many media companies, news included, the transition is difficult. Lonely Planet, of course, uses its website to sell print guidebooks along with pushing digital copies. It also makes money from online advertising and for connecting visitors with hotel reservations and insurance, among other things.

In five years, Palmer said that even more people will use tablets and smartphones to plan their vacations. But some travelers will still prefer analog over digital, contrary to predictions about travel guides heading for a quick extinction. “I think there will be a place for books,” Palmer said.

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