Google's location-tracking service, Latitude, uses the GPS hardware found in smart phones (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. I've been playing with the software on my BlackBerry for a couple of days, and I've taken the time to explore its features. Here's a guided tour of the Latitude experience.
Web Registration
If you already have a Google Account, you can get started simply by adding 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 smart phone 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.
Add Friends
Before Latitude can do you much good or harm, you'll need to add some friends with whom you'd like to share your location. Gmail users already have a heavily populated contact list to select from, but you also have the option to enter e-mail addresses manually.
Once you've added some friends, their avatars will appear on your 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 smart phones, 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.
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. I 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 Latitude. For instance, I'm toying with the idea of telling my friends that I'm in Timbuktu, Mali, because I want them to think I'm a hip jet-setter with a taste for exotic locales. (Sure, it's a stretch, but some of my friends are pretty gullible.)
Mobile Latitude
Unless all you want to do is track where your friends are all the time--which sounds sort of creepy, if you ask me--you'll probably spend a lot of time using Latitude's mobile interface. The interface varies a bit, depending on the device you're using it on, but this walkthrough of the screens on my BlackBerry Curve will give you a good sense of what it's like.
Google Mobile & Maps
On the BlackBerry, Latitude lives in the Google Mobile App, which you can download by browsing to www.google.com/mobile on you device. Even if you already have Google Mobile and Google Maps on your BlackBerry, you must download the latest version to get the Latitude features.
In Google Mobile, select Maps from the menu. If you have an older version of Maps on your phone, you'll be prompted to download an update now.
Initially, Latitude won't be enabled on your phone. Hit your menu button and then select Latitude to enable it. You'll need to enter your Google account user name and password, but afterward you'll have access to the features I discussed earlier in the Web interface section.
Mobile Friends List
The Friends list in the mobile version is just like the Friends list on the Web, except that it's slightly truncated because of the smaller screen. Instead of sitting off to the left of the map window, it hovers over the map, so you can't see what everyone's doing while you're looking at their position.
To add a new friend, click Press menu to add friends at the top of the Friends menu; you'll be taken to a screen that gives you access to all of the same contact list options that you had on the Web, including the option to enter new addresses manually. The Most Contacted option is quite helpful in this context, because it saves you from having to scroll through the names of hundreds of people you don't want to track or share your location with.
Friend Options
To customize the options for a given friend, highlight the person's name in the Friends list, and then press Enter to bring up the person's Options menu. Here you can get directions to the friend's current location (which could be unhelpful in light of possible spoofing), search for things near that location, adjust the level of sharing you'd like to enable for the friend, or dump the person from your Latitude tracking group.
Satellite and Traffic Views
Because it's built on Google Maps, Latitude has all of the same traffic reporting and satellite views you're accustomed to working with on your phone. Simply enable these options in your menu to see the corresponding details on your maps.
The Traffic view is especially cool when you want to see whether a friend you've arranged to meet will be on time. Just look for any red lines between that person's location and yours; such lines signify traffic delays. If the roads are all green, the friend will have no excuse for being tardy.
Quirks and Issues
Latitude is a brand-new service, and it's not without issues. But it's difficult for me to tell how many of these issues are the software's fault and how many are the result of the phone's underpowered GPS hardware. Mobile phones have long suffered from inaccurate GPS readings, resulting in all kinds of headaches with turn-by-turn directions and other basic location features.
It's not surprising, then, that Latitude often reports strange and inconsistent locations for its users. In my case, it generally showed my friends that I was several blocks--and sometimes several miles--from my actual position. Furthermore, it often bounced me around from one second to the next, showing me at my house one second, five blocks east the next, and then in a field a mile to the west a few seconds after that.
So while Latitude is an impressive little tool for keeping in touch with your friends, coworkers, and employees in real time, it's not exactly reliable if you're hoping to track them down to within a city block. Of course, anyone who is worried about privacy probably won't mind these little discrepancies at all.