title: iPhone: How to encrypt a string
body: <p>I would like to encrypt a string with AES 256 on the iPhone but have not found much via google.  What I am trying to do is post some data to a web site as part of a game I am creating, but I do not want the user to be able to cheat by seeing how it is posted because it is plain text.  So I want to post one encrypted string to my php page (ala www.test.com/test.php?encrypted= etc...) and then the php script will decrypt it and do what it needs to if it is valid.  </p>