What application do you use to send messages, the RC app or the SMS-Campaigns app?

If you use the SMS-Campaigns app, you can save the disclaimer text as a signature. And every time you create a campaign, enter the new text and load the signature and add to the message. It will add the disclaimer text to the end of your message. This will not automatically adding the signature, but it's more convenient as you don't have to type the disclaimer.