[It's funny she mentions that, because he has absolutely no idea what a cell phone is, seeing as he doesn't have context for a phone. He's gonna gloss right over that as not to be an absolute fool about it.]

Well, uhm-- yes, many things don't work the same here as they may have when you're at home. But if you're familiar, perhaps this will be easier. Simply press this and speak the name of the person you'd like to find, and if they are here, it will connect to their stone. That said, they will need to be listening for messages, so you may need to try a few times if you hear it connect but get no response.