CHICAGO (CBS) — A Chicago woman says it happened in minutes. She was walking home when a purse snatcher grabbed her and pulled her down the sidewalk.

As CBS 2’s Pamela Jones reports, what the suspect didn’t know is the iPhone in her purse had tracking software called “Find My iPhone”. The alleged victim tracked the suspect because, she says, police wouldn’t help.

“All of a sudden he ran towards me. Knocked me down while he grabbed my purse,” said Katherine Smith, “Then dragged me by my left arm because I couldn’t get the purse off fast enough.”

Neighbors called police, and Smith and her husband began tracking the suspect with “Find My IPhone.” The app uses a GPS signal to show phone owners where their phone is in real time.

The Smiths say they used the app to track the phone to a gas station at Pulaski and Division where they say the suspect was buying $100 worth of gas. The couple thinks the fuel was purchased with their money.

The couple says police arrived at their home within minutes, but did nothing after that.

“The cops didn’t seem very concerned or take a proactive stance and try to go out and do something,” said Katherine Smith.

“We showed them exactly where the criminal was on the map. Said he’s right here. And they did not go there. They didn’t call anyone. They didn’t send anyone,” said husband Kyle Smith.

So, the Smith’s say they did their own investigation and evenutally found the phone at a nearby cell phone store. They say the suspect sold the phone there. Police did arrive to help them get their phone back. But the Smiths want police to pull surveillance video from the store and from the gas station, so they might be able to make an arrest.

Police have not responded, so far, to our request for information on the case. The couple says they never found the stolen purse.

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