Many months ago I received a review copy of G-Map for the iPhone. It had its own maps and turn by turn directions, but no voice guidance, and North was always up. Apple was limiting nav apps at that time, and I had real trouble with G-Map. I couldn't load it on my iPhone. It kept locking up about halfway through the process. Extensive back and forth with the developers in Japan came to nothing, so I gave up. Finally, last April, my colleague Steve Sande was able to load it, and reviewed it for TUAW.

Now, with iPhones having new hardware and new software, G-Map [App Store] works and is certainly a competitor to the subscription-based AT&T app. You buy G-Map in one of several editions. G-Map West, at US$34.99, covers the Western States, and G-Map East covers, you guessed it, the Eastern U.S. It is also priced at 34.99. It gets a bit tricky, because some states like Illinois, Michigan, Tennessee and Wisconsin are split. If you travel all around those states you will probably want both editions.

There is also a California edition for $19.99, and one at the same price for New Jersey and New York. Versions for Canada and Europe are coming. All the G-Map modules require iPhone software version 3.0.

So how does it work? Pretty well, but with some caveats. It's accurate at getting your position. The voice directions are quite audible, especially compared to the distorted AT&T app. The on-screen display gives you your speed limit, distance to your next turn, distance to destination and time to destination. It also plots major intersections in a very detailed 3D view, which is helpful. This works in the largest 185 metro areas.

Another plus is that all the maps are on your phone. If you slide out of AT&T's service area the maps are still there; in contrast, the Telenav-based AT&T Navigator app will not work if you don't have data coverage, as the maps are downloaded on-demand.

There are some downsides. The POI database is pretty thin in smaller towns. From Southern Arizona it couldn't find the Phoenix Airport. It probably would have found it when I was closer, but even a POI search didn't bring it up. As I was sitting at a long established car wash, it said no car washes were nearby. It did better with restaurants, banks, and hospitals. Like the AT&T app, there is no landscape mode, and you can't get access to your address book, which is just plain silly.

It looks like the database, which comes from Navteq, has some errors, as do all such systems. Navigating to a restaurant, G-map reported it was on the left, when it was actually on the right.

Unlike the AT&T Navigator, G-Map has no real time traffic, but it does provide info from Navteq's traffic statistics to predict trouble areas.

Even with some weakness, G-Map is a worthy competitor to the AT&T iPhone app. If you have the room on your phone (G-Map West is 824 MB), you can navigate without worrying about cell network access.

It's cheaper than a monthly subscription would be over time, although there is no word when maps will be updated and what the cost will be. If the G-Map developers clean up the POI database, and add a lot more to it, I think they may sell a lot of apps. As it is, for getting to places where you know the address, it works about as well as the AT&T Navigator at a fraction of the cost. Of course more choices are coming, including the much discussed TomTom app, so you may want to wait it out and see what other offerings come along.

Here are some screen shots that show some of the major features:

I love GPS. in the mid 1990s I had a Garmin unit that had no maps, just a bread crumb trail of where you were and where you'd been. I lived in England at the time, and thought I had a highly original idea to take it to the Royal Observatory at Greenwich and walk across the Meridian line and watch the screen as the numbers dropped to zero longitude. When I got there, I was hardly alone. I was surrounded by other geeks doing exactly the same thing. Oh well.

GPS has come a long way, and AT&T has released their subscription based Navigator [App Store] for the iPhone. It requires OS version 3.0. It is fee based, and will set you back US$9.95 a month on your AT&T bill. It is loaded with features, and has voice guided turn by turn directions. It also offers:

• Automatic rerouting
• Updated maps with no additional charge
• Real time traffic updates
• Fuel Price searches and navigation to those locations
• Point of interest searches in all the usual categories like ATM machines, hospitals, restaurants, airports

The map gives you a 3D view from a position just above and behind your vehicle. On the setup page you can chose flat maps if your prefer. I found the maps easy to read but would have preferred a landscape view instead of portrait (there is no option to change the orientation). I saw a little lag when driving, but generally the response was fast.

The app really needs a 3G connection. It works on the EDGE network, but was slow to load graphics. If you are somewhere where you have neither you are out of luck. No maps are contained on the app and nothing is cached. In essence, the app is only as good as the AT&T network, and if you do a lot of driving where the network is weak or absent, you'll be navigating on your own.

I found the voice very hard to hear. This is a limitation of the iPhone speaker. It just wasn't designed to be played at a loud volume. On the highway, with road noise, good luck hearing that warning to turn. Of course, the directions are on the map, but the whole purpose of voice instructions is to keep you from looking at the map.

Other features are a high altitude view of your entire trip from beginning to end, a list of your turns on a scrollable page, directions to the nearest AT&T WiFi hotspots (nice), and the ability to set your default navigation method like shortest, fastest, traffic optimized, prefer highways or streets, or pedestrian routing if you're not driving.

I found the voice alerts were too frequent. Frankly, the app is a blabbermouth, and it kept reminding me of a faraway turn too often for my taste. It would be nice to be able to set just how aggressive the voice warnings are.

The big question for most iPhone users will be whether to wait for other nav apps to appear. TomTom is imminent, as is an app from Navigon. They both download the maps to your phone, so you are not dependent on the AT&T network. You only need GPS, and that signal is everywhere. You could also buy an inexpensive dedicated unit; on the low end that will cost about the same as a year of the AT&T subscription, and will certainly have a better speaker. Of course, there will be fees to update the maps, but in my experience you can use a GPS for years without doing that. Points of interest change, but the iPhone provides other sources like Google for up to date info.

I also think it is a bloody shame that the AT&T app has no access to your address book. Apple has walled that data off from 3rd party apps, (Update: Apple provides the ability, the Navigator app hasn't implemented it) and it is just senseless to have you type everything in again. You can copy and paste the data, but it is a needless pain. The AT&T app has this access when it runs on other phones like the Blackberry.

In summary, the app works, and is feature laden. I'm not sure it is the best option for in-car navigation, and you might want to wait for other solutions to appear. Of course, you can always get the AT&T app and cancel. It's a month-by-month charge.

So how is it like to drive with this app? My colleague Steven Sande did just that, and his report will follow soon.

Before you go, here are some screen shots to give you a look at some of the features on AT&T Navigator: