Rather than decide whether to reach someone at home, at work, or on a cell phone, callers can use the person's Google Voice number. The service , which is currently available by invitation only, also allows a user to manage how he or she can be reached by different callers.

Apple's rejection of Google Voice, submitted six weeks ago, blocks features that compete with or duplicate iPhone features, and potential users are not happy. Allowing the Google app could take money out of Apple's and wireless carrier AT&T 's pockets.

"We work hard to bring Google applications to a number of mobile platforms, including the iPhone," said Jew-Lim. "We will continue to work to bring our services to iPhone users -- for example, by taking advantage of advances in mobile browsers."

Users Upset

Developer Sean Kovacs also had his GV Mobile app rejected. "Looks like Apple/AT&T pissed off a lot of people," Kovacs wrote on his blog Tuesday.

He wrote that Richard Chipman from Apple called him on Monday and said Apple was removing GV Mobile from the App Store because it duplicated iPhone features. He said Chipman didn't specify which features were rejected, but assumes the entire app was rejected.

Users of the Google service are not happy, including a poster named Yuusharo who said Apple's move stifles innovation on the iPhone.

"Everyone is so pissed off at AT&T, but let's be real for a moment. Apple was the one who pulled the application, not AT&T," Yuusharo wrote. "Many people somehow think that Apple is beholden to these partnerships, when the fact is Apple controls the shots here."

Kovacs said he will release GV Mobile v1.2 on the Cydia Store for jailbreakers, with an update coming later.

"Why free? People pirate it anyway, so why not?" he wrote. "I do appreciate everyone that bought it -- you are the ones that fueled this app to be what it is today."

Others Welcome App

Although Apple iPhone users are blocked from Google Voice, other mobile-phone users are benefiting. Users of Research In Motion's BlackBerry smartphones and phones with Android-based operating systems are welcoming Google's app.

The app allows users to place calls and SMS messages directly from the Google number. Users can place calls using their phone's address book or enter in numbers.

But will Google Voice's availability on other mobile platforms be enough?

"The HTC Hero is not enough to pull me away from my iPhone just yet, but if it's any indication where Android will be a year from now, it's looking mighty attractive," Yuusharo wrote.