With the iPhone Share Contact tool, you can easily send the contact information of anyone in your phone book to another iPhone. Instead of sharing contact phone numbers via text message digit by digit, you can simply use the "Share Contact" button. This sends the contact card of the person whose information you wish to share via MMS. Both iPhones must have the MMS feature to accomplish the share successfully.
Launch the Contacts application from your iPhone home screen.
Tap the name of the contact you want to share. His information page loads.
Tap the "Share Contact" button. A prompt opens.
Select "MMS." The iPhone's text messaging application loads with the contact card already inserted as the body of the message.
Tap the To field, then enter the number of the other iPhone.
Tap "Send" when you are finished to share the contact.