This post shows the basics for sending an SMS message from within an iPhone application. The class you'll need to use is MFMessageComposeViewController which presents the standard SMS interface for composing and sending messages. As you'll see in the example that follows, you can also pre-populate the body of the message as well one or more recipients for the SMS.

SMS View Controller Interface

The view controller that will send the SMS is shown below, notice the message composer import statement as well as the reference to the protocol MFMessageComposeViewControllerDelegate. The delegate has just one method where you can check the result of the message (sent, cancelled or failed) and this is also where you dismiss the view controller show the message composer – more on this method in a moment.

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