Extending its pay-per-call ad network to include text messages, Ingenio will be providing sponsored listings to UpSNAP's SMS-based directory assistance service FREE 411, writes ClickZ. Users will see the pay-per-call ads only when they search for a listing in a sponsored category. However, UpSNAP does not identify which of its listings are sponsored, an approach CEO Tony Philipp likens to that of Yellow Pages.

Marc Barach, Ingenio's chief marketing officer, said "pay-per-call as an advertising model has legs beyond Web search…there are environments where a click is just not a suitable event - on a mobile device for example [where] call-through rates…are substantially higher than in the web environment."

UpSNAP will deliver as many as four listings within a text message, but only sponsored links are enabled with a "click to connect" button. Ads may also appear on the UpSNAPs partner network and on its other text messaging services.