Talk about leaving a trace.
Shortly after the theft, the suspect posted a close-up photo of himself making a bizarre expression on the victim's Instagram story using the stolen phone.
The photo showed a bearded man with brown eyes, glasses and wearing a green fleece or jacket.
Authorities said they were turning to Facebook for help in tracking down the suspect.
Anyone who can help identify the person is asked to contact the Kearny Police Detective Bureau by emailing firstname.lastname@example.org or by calling 201-998-1313 (2833).
All tips will remain confidential, according to police.