Castle: Alexis said she'd be in the Village today, but she's over in Williamsburg.
Beckett: Well, how do you know she's in Williamsburg?
Castle: GPS tracked her phone.
Beckett: You tracked her phone?
Castle: Yeah. Super cool app I just downloaded. I can see where she is at anytime.
Beckett: Does she know that you're doing this?
Castle: What, are you kidding? No, she'd kill me.
Beckett: And be justified.