The context of the following conversation is Robin used Tracy's device to find her phone and then returned the device after finding it.:
Tracy says You know how Robin's phone has that phone finder app?.
The friend responds Yeah, what about it?.
Tracy responds Well I saw how it works. She couldn't find her phone and borrowed my device to use the app to find it..
The friend responds Why didn't she just call the phone?.
Tracy responds It was dead, the app can find a phone that is not charged..
The friend responds Oh, that's cool..