This app lets you  organizing contacts automatically by creating smart groups.  A Smart Group is updated automatically based on criteria you specify. You can send email and text/sms to smart groups on the fly.

Feature list:

Send Group SMS/Text and Email

Assign contacts to multiple groups at a time

Support customized templates and signatures

Support distribution list management

Manage Smart Groups

Smart Groups can automatically organizing information in your address book. The possibilities are endless with Smart Groups. They can be used on any of the criteria stored and will auto-update whenever a change is made.