Both of my boys have/had iTouches. My oldest no longer has one, but when he did, he used TextNow, an app that assigned him a number to text. My youngest, who just got one for Christmas, uses an email address to text. It's an address I set up for him, and I have the password. I just logged in to see if it shows any texts sent or received, and there's nothing. I wonder how they can trace that.