TXT Group is the simplest way to organize your contacts into groups and send messages to all of them at once. The built-in character counter lets you know when you are reaching the 160 character single-message limit. You can easily add or remove attachments, and the preview is larger than the Messaging application. Use the Quick Text feature to quickly send pre-configured messages. Best of all, it's FREE! There are no limitations to the number of groups or users you can add. Donations of $1 or more will remove advertisements (anything additional can be used for multiple devices).

TXT Group screenshots: