Google announced it has bought Zagat Surveys, the online restaurant rating and reviewer, to bolster its search service. The transaction will augment its move into smartphones, coming after its deal to acquire Motorola Mobility.

The transaction fee was not disclosed by the Mountain View, Calif.-based search-engine giant. Google's cash and investments exceeded $39 billion in the second quarter.

The Google-Zagat takeover is also targeted at other online services such as OpenTable, which completed its IPO in May 2010. OpenTable shares fell 11.41 percent to $55.57 on the news. The Zagat purchase also bolsters Google's offerings against various apps Apple has been selling from its App store. It also means the search giant will be positioned against traditional publishers like New York Times which allow paying subscribers access to restaurant reviews.

Zagat will be a cornerstone of our local offering, delighting people with their impressive array of reviews, ratings and insights, said Google VP Marissa Mayer in a blog post.

Zagat's Web site has already taken on the Google logo. The service says the takeover can optimize the potential of the Zagat brand while offering 'new ways' for consumers to 'express their opinions' and 'make informed decisions.'

Zagat had been owned by former stock analyst Tim Zagat and his wife Nina, who created it in1979. They hired Goldman Sachs to help find a buyer in 2008. In the current sale, Zagat hired Peter J. Solomon and Allen & Co. for advice.

Zagat had collaborated with Google as well as with Facebook and Foursquare in the past.

On her blog posting, Google's Mayer chirped: Foodies have more fun! Both Zagats will continue to be involved with their service.

Google shares rose $3.18 to $537.33 after the Zagat purchase was disclosed.