ROBERT SIEGEL, HOST:
We end this hour with a bit of tech news about your phone and a problem that has long confounded the mobile industry. It's known as the fat finger problem.
(SOUNDBITE OF TV SHOW, "THE SIMPSONS")
UNIDENTIFIED WOMAN: The fingers you have used to dial are too fat. To obtain a special dialing wand, please mash the keypad with your palm now.
MELISSA BLOCK, HOST:
That's Homer Simpson experiencing the fat finger problem firsthand. While our fingers aren't getting any smaller, the buttons on our smart phones are. That means we dial a lot of wrong numbers, it also means when we surf the Web, we inadvertently hit an ad and get whisked away to some sponsor's website.
JONATHAN ALFERNESS: If you think about the tip of your finger and you think about how much screen real estate the tip of your finger takes up on even a modern, larger cell phone screen, right, it's a nontrivial amount of space.
SIEGEL: That's Jonathan Alferness of Google. And mobile ads are anything but trivial for the tech giant, which makes most of its money from advertising. Estimates vary, but it has been reported that 20 to 40 percent of all mobile ad clicks are accidental. And Alferness says that's a problem.
ALFERNESS: It was one of the things, I think from an industry point of view, that was holding back advertisers from wanting to spend on mobile advertising.
BLOCK: Well, to fight the fat finger problem, Google has just rolled out a new type of mobile advertisement. It involves image banner ads, the kind you often find at the top or bottom of your smart phone screen when you're using a free app. But now, if you accidentally touch the border of the ad, it asks you to confirm the click before whisking you away.
ALFERNESS: It's just the edges of the ad that start to act as a no man's land of sorts. And that's when we know to prompt user for more.
SIEGEL: Google's Jonathan Alferness says the new ads are a win for advertisers. And yes, he says, they may get less traffic to their sites, but...
ALFERNESS: The rate at which we are converting, that is turning these users into true customers for our advertisers, is increasing because I'm only looking at a set of users who are actually interested in the advertisement.
SIEGEL: And that's not just a win for advertisers, it's a win for all of us and our fat fingers. Transcript provided by NPR, Copyright National Public Radio.