With Google Latitude, you can:
- See where your friends are and what they are up to
- Quickly contact them with SMS, IM, or a phone call
- Maintain complete control over your privacy
Latitude is a new feature of Google Maps for mobile, as well as an iGoogle gadget, that allows you to share your location with your friends and to see their approximate locations, if they choose to share them with you. You can use your Google account to sign in and easily invite friends to Latitude from your existing list of contacts or by entering their email addresses. Google Talk is integrated with Latitude, so you and your friends can update your status messages and profile photos on the go and see what everyone is up to. You can also call, SMS, IM, or email each other within the app. [Source]
To get started visit google.com/latitude from your phone's mobile browser or add the Latitude gadget to your iGoogle homepage. Let me know what you think, do any of your friends even play Tennis :)