Google launched a Google Voice for the iPhone application Tuesday after a lengthy dispute with Apple that drew the attention of US government telecom regulators.

Christian Brunschen, a Google software engineer, said in a blog post that Google Voice for iPhone was available for immediate downloading from Apple's online App Store.

"We're taking the Google Voice experience on the iPhone to a whole new level with the launch of the official Google Voice for iPhone app," Brunschen said.

Google Voice allows users to merge their home, office and mobile phones into a single number. It also allows them to make cheap international phone calls, send free SMS messages and provides transcripts of voicemail messages.

The service is only available in the United States for the moment and requires a Google Voice account.

Google and Apple got into a tussle last year over Google Voice for the iPhone with the California gadget-maker arguing it usurped core telephone features designed into iPhones.

The dispute drew the attention of the US Federal Communications Commission which sent "inquiry letters" about the Google Voice for iPhone application to Apple, Google and AT&T, iPhone's exclusive carrier in the United States.