This information has been posted here before, but here it is again:
"This is a new arena for us. That's part of the reason we called the FBI in. It's probably pretty new to them, too," Mitch Mortvedt, spokesman for the Iowa Division of Criminal Investigation, told
CNN. "I don't know of another case here in Iowa where we have used specifically Fitbit info."
When her Fitbit pinged at a hog farm about 10 miles southeast of the house in Brooklyn, IA, where she was last seen, police searched the area but found nothing, Mortvedt said."
Everything We Know About The Disappearance Of Iowa College Student Mollie Tibbetts
I believe the word "ping" references a digital signature. Police admit that this is a "new arena" for them, and they may not use the best words to reference the digital evidence.