Google's much-anticipated location-tracking service, Google Latitude, uses the GPS hardware found in smartphones (such as Google Android phones and BlackBerry and Windows Mobile handsets) to pinpoint your position on a map and share that information with your friends. Here's a guided tour of the Latitude experience.
Google Latitude: web registration
If you already have a Google Account, you can get started simply by adding Google Latitude to your iGoogle page on the web. If you take this approach, you can use your full keyboard and mouse to populate your Friends list. Alternatively, you can browse to google.com/latitude on your smartphone and download the latest version of the Google Mobile app, which has Latitude functionality built in. Once it's on your phone, you can log in and get started.
Google Latitude: add friends
Before Google Latitude can do you much good or harm, you'll need to add some friends with whom you'd like to share your location. Googlemail users already have a heavily populated contact list to select from, but you also have the option to enter email addresses manually.
Once you've added some friends, their avatars will appear on your Google Latitude map. You'll also be able to see how long ago they last updated their location, either by clicking their avatar in the map view or by looking at their listing in your Friends list.
If your friends haven't entered a location for themselves and haven't enabled GPS tracking on their smartphones, you'll just see 'Unknown Location' by their names. In some cases, you'll also see a tiny icon that looks like an eyeball with a slash through it. You might think that this means your friend has chosen to hide his or her location from you, but it actually means the opposite: the friend can't see your location. In this case, you'll need to select that friend and enable the level of location sharing you want to confer.
Google Latitude: privacy
You have three options for sharing your location: you can have Latitude detect your location to the best of its ability and automatically share it; you can set your location manually by entering an address or city; or you can hide your location entirely. You select the option you want in the oddly named Privacy menu. We think that a better label would be Location Sharing, which describes what actually happens here.
This menu sets your sharing preferences universally for all of your friends. If you like, however, you can change your sharing options for each friend individually. More on this later.
Because you can enter any address you want when you set your location, it's very easy to spoof your position with Google Latitude. For instance, we're toying with the idea of telling people that we're in Timbuktu, Mali, because we want the world to think we're hip jet-setters with a taste for exotic locales.