Just a couple weeks ago we brought you news of the new turn-by-turn GPS navigation software that would be coming to the Apple iPhone with the just-released OS 3.0 update, and now AT&T, the official carrier of the iPhone in the U.S., has released its official app, for free - but with a string attached.

That string is a $9.99/month service charge. While it's a slick way to distribute the high initial cost necessitated by the complex software and map licenses, it's also a recipe for spending more than the price of a standalone GPS unit over the course of a year or two.

Nevertheless, AT&T is geared up for widespread adoption of the app, and has built a feature-packed experience to ensure users are satisfied. The software, written by Telenav GPS, has already been available on a number of phones and carriers, including the competitive Google Android-based T-Mobile G1.

"With the new iPhone OS 3.0 software, we're expanding the advantages of true turn-by-turn navigation - both voice and on-screen directions - to millions more customers. We're bringing greater convenience to drivers and travelers nationwide, including providing regular, automatic updates to map information at no charge so customers have the latest at their fingertips," said AT&T's Mark Collins, vice president of voice and data products.

So how does it rate as an actual GPS device? The initial reports are good, with voice prompting, points of interest, automatic re-routing, speech recognition, and on-screen controls and displays all easy to use, complete and familiar. One weakspot: no mounting hardware is made available with the app, so you'll have to source your own if you want to put the new AT&T Navigator software to use on the road.


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