Groups! Free

You've just found the best, easiest tool for communicating with your iPhone contacts.
Downloaded by 2.6 million people in over 100 countries around the world.
Don't take our word for it. See for yourself! It's free.

Groups works with your native contacts and phone capabilities, so it's completely private.

MANAGE
  + Group your contacts into Friends, Family, etc.
  + Easily create and manage any groups of contacts
  + Now translated into 15 languages!
  + Works with native iPhone groups
  + Set an icon for each group - now w/more icons!

COMMUNICATE
  + Easily text or email many contacts at once
  + Works even if your contacts don't have the app
  + Personalize your texts with first name, last name, etc.
  + Attach images to your emails, use To | Cc | Bcc
  + Share your location with people you're meeting

FIND
  + Search within groups, by any attribute
  + Set reminders to get in touch with people
  + Quickly build lists of people to contact
  + Supports all iPhone screen sizes 
  + Takes advantage of the latest iOS features (like Do Not Disturb, Voice Messages etc.)

Notes for iOS 7 and iOS 8 users:
* Groups will obviously need to access your contacts in order to work.
* If you have iMessage turned on, your phone will use it to send out group messages.
* iOS 8 has much improved Group Texting capabilities that Groups can take advantage of.