This undated screen shot released by Tapulous shows a new finger-tapping music application for the iPhone called "Tap Tap Revenge: Metallica." In the game, players tap areas on the screen in time with the music, much as players strum or drum plastic instruments in video games such "Rock Band" and "Guitar Hero," except on a smaller scale. (AP Photo/Tapulous)

Rock band takrs part to stay relevant with today's youth.

LOS ANGELES (AP) — Headbangers will have a reason to steady their gaze a bit starting Tuesday, when rock band Metallica makes its way onto iPhones with a finger-tapping music app called "Tap Tap Revenge: Metallica."

In the game, players tap areas on the screen in time with the music, much like players strum or drum plastic instruments in video games such as "Rock Band" and "Guitar Hero," except on a smaller scale.

The iconic rockers could probably make more money performing one or two shows live, with 10 playable songs on the game, including "Enter Sandman," selling for $4.99.

But the band took part to stay relevant with today's youth, said drummer Lars Ulrich, 45, the father of 11-year-old and 8-year-old boys.

"It's one more thing that'll keep me semi-cool in my kids' eyes for another six months until the next thing comes out," Ulrich said. "It's not about the money or revenue or some master plan. This stuff all falls in the fun category."

Last year, Metallica released its new album "Death Magnetic" through the "Guitar Hero: Metallica" video game as well as traditional outlets.

Metallica's recording company, Warner Bros. Records, expects the game to make it into the top 10 paid music apps on Apple Inc.'s iTunes store.

"We're not expecting this to be some sort of golden miraculous thing that changes the economics of record labels," said Jack Isquith, senior vice president of digital music for the unit of Warner Music Group Corp. "The main driver was to have it stand up to scrutiny from hardcore Metallica fans now. We think it's a cool game."

"Tap Tap Revenge 3," by Palo Alto-based developer Tapulous Inc., is already the top paid app on the store, and more than 16 million downloads of different versions of the game, most of which were free.

Close to a million premium versions, featuring bands such as Lady Gaga, Coldplay and Nine Inch Nails, have been downloaded for $4.99 each.

Tapulous is a private startup that began with around $3 million in capital the same time the app store launched in July 2008.

It shares 30 percent of its sales with Apple and splits the rest between itself and recording and music publishing companies.

Tim O'Brien, Tapulous' head of business development, said the company has been profitable since June.

With its latest version priced at 99 cents and other goods on sale, such as song downloads and virtual bombs to slow opponents, O'Brien said, "We expect to maintain profitability from here on out."