The girl told police that Cesmat had taken away her cell phone away when she went to bed, telling her he did not want her texting all night.
So the girl had no phone, just her iPod, which I assume was an iPod touch. She wasn't able to make a call from it, or an SMS, but she could send a Facebook message (or an email, or with the right software an IM to pretty much any service).
This is a story about how important communication can now be made by devices other than a phone. Or how children now not only have a mobile phone, but often a second gadget capable of keeping them connected.
And it's not like she didn't use Facebook and an iPod.