Google Latitude: Tell Your Friends Where You Are

Ever wonder where your friends or your spouse or your child is? That’s the question Google hopes to answer for you with a new service launching Wednesday called Google Latitude.

Using a combination of Global Positioning System, WiFi, and cell tower location data, the service, an extension of Google Maps, Latitude can determine where you are in the world via your mobile device depending on which of those technologies the device can use. It will work on most color Blackberries, most Windows Mobile 5.0 devices, most Symbian S60 devices, and phones powered by Google’s Android mobile software, such as the T-Mobile G1. No iPhone or iPod Touch yet, but Google says that’s coming very soon.

The service wasn’t yet functional when I was briefed by Google, so I can’t yet vouch for it, but here’s how it works: You download a new version of Google Maps onto your mobile device, then invite friends via an email to join. Once they accept, and if they have a Google account with a profile picture, you’ll see that on a map. Then you can send them an email or text message or call them, and of course get directions to their location. You can also view locations of your friends from your desktop through iGoogle, the company’s personalized home page.

The service sounds a little like Dodgeball, the location service that Google bought a few years ago, only to announce recently that it will shut it down. But Latitude was developed by the Google Maps team with different technology, and it’s an extension of Maps rather than an entirely separate service. It also goes further than My Location, a Maps feature introduced in late 2007, which let you see your own location on a map. But Latitude also follows similar services such as Loopt.

In some ways, it might seem like yet another way for 20somethings with a lot of time on their hands to party spontaneously with their friends. But in three months of testing inside Google and with “trusted testers” outside the company (including the Wall Street Journal’s Mossberg Solution columnist Katherine Boehret), broader use cases emerged. If you’re home and wondering when to start making dinner, you can tell when your spouse left work to time it right, even if he or she doesn’t remember to check in. Parents of adult children can feel more connected to their offspring knowing where they’re traveling.

Of course, the obvious question is: Isn’t this just a fine stalker tool? Not surprisingly, Google thought about this a lot, and offers a wide variety of ways to make sure you can’t be tracked if you don’t want to (and a readymade quote from Cindy Southworth, firector of the Safety Net Project at the National Network to End Domestic Violence, saying she worked with Google on the privacy aspects). The service is opt-in, and you can control precisely who among your friends and relatives can see your location. You can hide your location from everyone or particular people, opt to share only the city you’re in generally, or just turn the service off.

I can imagine this kind of information would help Google advertisers target local pitches to you eventually, but Google says it has no specific plans for this yet.

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