Fon11 uses phone numbers to link you to your contacts

What Company Is Offering:
Fon11 uses phone numbers to link you to your contacts. To add a contact, you'll need to enter the person's phone number(s) and invite him or her to do the same for your number(s). Please note, to protect your privacy, Fon11 will only link one number at a time. This means if someone typed in your office number, they won't see your mobile and home phone numbers.

You may add as many contacts and numbers as you like, however, until the other party adds you to their contact list, you won't be able to share photos and messages.

How It Works:

Sign up for an account. After you sign in, go to Settings (at the bottom of My Info page) to set up your phone numbers. If you chose to share your location, you may also enter addresses there.
All contacts in your list can see your availability, mood, and message.

For sensitive information, such as your location, you are in full control of how much to share. For instance, you have 4 ways to share you location: (1) Street level - your exact location, (2) Neighborhood level - or within two kilometers, (3) Metro level - the metropolitan area you are in, or (4) Hide your location. If you choose to hide your location, you will not appear on your friend's Nearby page.

More at:http://www.fon11.com/