Smartphone apps can do just about anything these days.
One man even used his to watch his stolen car drive away.
Authorities say the car and his phone were stolen from his friend's driveway Christmas morning.
But his phone being in his car was actually a good thing.
He uses an app called "Find my iphone," which taps into the phone's internal GPS to track it down.
It will send you an alert and show you where it is.
He tracked it to a small service station in Justin and then called police and led them right to it.
But it wasn't over yet.
"She called me back frantically and she said I need you to track your car again right now. And she said stay on the phone with me and tell me exactly where it is. She said he just ran over the officer," car owner Whit Snell said.
Snell followed that blue tracking dot on his computer all the way to Wise County, where police caught up with the SUV and it later crashed.