It's a device, that can send messages to everyone, who is stuck here like you. And then everyone can answer to your messages.

Kinda like a phone, but with a tiny screen where you see the other person? And like a camera that can record videos.

[No, seriously, she's a mechanic and it's still weird to explain all the things of this world to people without this kind of technology... orz. But it was new to her too at first, and she doesn't explain it often, shhhhhhh.]