WEATHERFORD (CBSDFW.COM) – In a time when phones aren’t attached to anything, it can lead to that annoying problem of having to find them.

Just ask Dee Probst: She called her phone 39 times when it disappeared Friday in a Weatherford store. When it didn’t turn up, she didn’t give up.

Instead, she and her son turned to private investigators, with the help of a simple technology that anyone can download, for free.

“We couldn’t ever find it and so I called Brandon because I knew he had a tracker on it,” Porbst said.

Brandon Horn is Probst’s son, who had three of his electric company’s trucks broken into last year.

He tried to get the cell phone company to track the computers the thieves took but could never narrow down exactly where they were.

When he replaced the equipment this year, he installed all the computers and phones with “Find My Phone,” a free app from Apple.

Using GPS it shows you on a map exactly, where you left your phone or laptop.

It allows you to add as many devices as you want, including those of your friends and family.

So Probst knew her son could figure out where she left hers.

“We were looking everywhere and we were going all over it, and he finally said, Mom, your phone just left the store,” Probst said.

In that instant, mother and son realized they weren’t tracking a lost item, but a stolen one.

Rather than back down, Horn drove from Denton to Weatherford, all the while watching his computer to see if the phone moved again.

He would relay updates to his mom, who was writing down the license plates of any cars that left the parking lot she was in, in case they had the phone.

After more than an hour, Horn parked his truck right directly on top of the spot on the map where the app showed the phone was located.

“As I get out of the car, I looked in the car next to me, it’s in the front seat,” he said.

Inside a pink case, the phone was sitting inside a stranger’s red car.

Horn called it, and saw his name pop up on the face.

Only then, to retrieve it from a strangers car, did the pair have to call police.

Officers waited about 20 minutes for a woman to come to the car, and then they retrieved the phone.

They’re still working on charges for the woman who had it.