The words iPhone and thrifty are rarely said in the same sentence. But for consumers looking to save a few cents on long distance calls, Talkster is enabling global group conference calling for the cost of a single local call. Where's the catch?

Audio advertisements, of course -- but they will be targeted and last only 10 seconds. Such is the brainchild of Talkster, a provider of free long distance, international and conference calls.

"A lot of people are going to be getting iPhones for Christmas and wanting to speak to friends and family," said James Wanless, cofounder and chief operating officer of Talkster, Toronto. "The people who are getting the iPhone this Christmas are going to be looking for more things they can do, saying, 'What can I do with this that I could not do with my old regular phone?'"

The iPhone already enables users to add callers into an existing conversation with an intuitive Add button that appears on the touch screen. But if the user consistently communicates with the same group, adding others over and over again can become tedious. Also, every additional caller adds to the fee for the call.

"When you're adding callers on the iPhone, it actually becomes a multiplier for the number of minutes you're using," Mr. Wanless said. "So if you're getting into longer calls that can add up, and if you're making calls internationally, that can become extremely expensive."

Talk is cheap
Talkster offers callers free long distance, international and group conference calls from any kind of phone by subsidizing the cost of calls with ads. Callers listen to a single, 10-second audio ad at the start of each call and then can talk as long as they like with free calling service and no talk-time limits in more than 30 countries.

"It actually works on any mobile phone," Mr. Wanless said. "We're looking at people who have the iPhone because they're the early-adopter people. But when we look at the type of people they communicate with, they may have a different device."

The ads are targeted to the location of the persons on the call. For example, if three conference callers are from New York, Los Angeles and London, they will each hear a different message.

While many marketers are looking for traditional banner advertising on mobile applications, they should be aware of the "banner-blindness epidemic," Mr. Wanless said.

The company plans to enhance its audio ads to include instant call to action. Just by pressing the star button, callers will be able to get a coupon on their phone that they can take into a store and redeem directly.

"We just launched a few weeks ago," Mr. Wanless said. "As we build out the service and we add more features, we will get more demographic information and we will use that to give more than an ad -- to turn it into an offer."

IPhone users can go to http://i.talkster.com to set up their group call by entering the names and phone numbers of the people they want to call and then click "Invite." Talkster generates a local phone number for each of the call participants and distributes the new number via text message. Callers can save the number in their address book and use it any time they want to talk to this same group of people.

"We are looking to have an application that can be installed on the iPhone so that users do not have to go to the site," Mr. Wanless said.