Google Click-to-Call was a service provided by Google which allows users to call advertisers from Google search results pages. Users enter their phone number, Google calls them back and connects to the advertiser. Calling charges are paid by Google. It was discontinued in 2007. For some time similar click-to-call functionality was available for results in Google Maps. In the Froyo release of Google's Android operating system, in certain advertisements, there is a very similar functionality, where a user can easily call an advertiser.
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