*Update 11/15/2009* There are now several apps that let you create and edit groups on the iPhone. Some examples are Groups (iTunes link), YoContacts (iTunes link), and iGroupMail (iTunes link)
To create a group of contacts for your iPhone, you must use the program Address Book that ships with every Mac. To create a group, open the progam, Click File, and select New Group:

A group is made up of multiple contacts, and only those contacts appear on screen when you select the group. For example, you could label all your family contacts under a group called “Family.” A group like this could come in handy if you wanted to make calls to all your family members in an emergency or to make an announcement.

Groups created in the Mac program Address Book
For now, groups cannot be created using just the iPhone, nor can you remove a contact from a group. The only thing you can do with groups using the iPhone is create a new contact inside a group. For instance, if you navigate to the group “Work,” and create a new contact by tapping the “+” icon, that contact will be added to “Work.” Hopefully, the option to create and edit groups using the iPhone will appear in the future.
Helpful Link:
Discussion of groups at Apple.com.


#1 by Rudytaylor3rd@mac.co on October 6th, 2008
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After the group has been synced to Iphone I cannot remove it from phone even if I delete in address book? If so how.
#2 by Alan on January 17th, 2009
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Delete the group from the address book, synch the iPhone, and it will disappear from the iPhone.
#3 by Dax on November 15th, 2009
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Can you send a text to a group all at once? I want to type one message and send it to the whole group, is that possible?
#4 by maple on April 20th, 2010
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Hi, you can try the ZZ communication application to manage and group your contact. Below is the link in iTune Store.
itms://itunes.apple.com/us/app/zz-communication/id367020305?mt=8
#5 by lou on May 18th, 2010
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Does this work with “smart groups”? On my iPhone, it appears that smart groups don’t work.
#6 by Sandy on May 26th, 2010
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I have a PC, how do I create a group from my PC. Also, there are groups that have not contact in them, is there a way just to change the name of the group and start adding contacts there?
#7 by dave on June 11th, 2010
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why is apple so behind on contact management? HTC puts the iphone to shame, in this department… I want to switch to the iphone but man, group contacts should not be this difficult! It is AUTOMATIC with htc and google, and intuitive.
#8 by nguret on August 23rd, 2010
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Hey !
still no method to edit groups just with the iPhone ?
#9 by Alan on August 24th, 2010
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Nope, unfortunately editing of groups did not arrive with iOS 4. You still have to rely on third-party apps.