An out-of-town visitor played detective last week, using the “Find My Phone” app on his iPhone 4S to find the man suspected of stealing it.

Thanks to the fast thinking of Timothy Semon, a New York City resident who was staying at the Comfort Suites Hotel at 601 Main St., Charles Thompson, 46, of Leroy Avenue, was arrested after the 1:30 a.m. Wednesday stickup, police said.

Police said Thompson accosted Semon as he left the hotel and told him he had a gun, forcing the victim to surrender his cellphone and a number of credit cards. Thompson then got into a car and drove east on West Chippewa Street. Semon quickly initiated the “Find My Phone” app on his cellphone and told police to go to 55 N. Johnson Park.

Thompson was arrested there and, when taken back to the hotel, was positively identified by the victim, police said.

Police recovered the six of Semon’s credit cards in Thompson’s right sock.

But the victim’s cellphone was not located. Police believe Thompson quickly sold it.

Thompson was jailed on charges of first-degree robbery, criminal possession of stolen property, felony grand larceny and criminal possession of a controlled substance because of a glass crack pipe he was allegedly carrying.