A recent feature to Google Adwords is their Click to Call feature.

This feature allows advertisers to display a phone number as a link alongside their Adwords advertising to users searching on Mobile devices.

This allows users the option to call the number displayed alongside Adwords ads as an alternative to clicking through to the advertisers website.

Advertisers pay for a phone call rather than a click to their website.

The phone call requires a 2-step process; first a user needs to click on the phone number link, and then secondly needs to agree to call the number.

Display scheduling can be set so that Click to Call links only appear during hours of operation so that unanswered calls are not paid for.