Google Latitude: mobile Latitude
Unless all you want to do is track where your friends are all the time - which sounds sort of creepy - you'll probably spend a lot of time using Google 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 Latitude: 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 your 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, Google 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 we discussed earlier in the web interface section.
Google Latitude: mobile friends list
The Friends list in the mobile version of Google Latitude 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.
Google Latitude: friend options
To customise 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 Google Latitude tracking group.