Google Latitude lets a user share his or her physical location with friends, and locate friends on a map, the company said in an announcement Monday.
"You can see where your friends are and now, continuously share where you are ... even in the background once you've closed the app," said Chris Lambert, a software engineer on the Latitude team, in a post to a Google blog .
Google launched Latitude in February 2009, a beta appeared the year before for smartphones running the Android operating system, as well as devices powered by Symbian, Windows Mobile and Research in Motion's BlackBerry. At the time, Google said that an app for the iPhone was "coming soon."
Previously, Latitude was available to iPhone owners only as a web-based application, which could not take advantage of iOS 4's limited multitasking. "Today's Latitude app was built from the ground up using iOS 4's new multitasking capability to support background updating," said Lambert.
At times, Google and Apple have had a prickly relationship over apps.
In mid-2009, the former submitted Google Voice to the App Store, but Google claimed Apple rejected the program because the call management software replaced some of the iPhone's "core mobile telephone functionality." In a response to inquiries from the Federal Communications Commission (FCC) during a short-lived investigation into its App Store practices, Apple denied that it had rebuffed Google Voice, telling the FCC at the time that it "continues to study" the software.
Google Voice finally appeared in the App Store in November , 17 months after Google submitted the program.
Apple posted Google Latitude to its iTunes' App Store on Monday. The app is a free download.