The Valley Brook Avenue victim found the phone after noticing a light coming from a corner laundry basket as she emerged from a shower, Detective Lt. Vincent Auteri said.
She notified police, who arrested Hirotaka Aida, 58, on invasion of privacy charges, he said.
Given consent to search his room, detectives found SD cards and thumb drives that were seized to be examined as possible evidence, Auteri said.
Aida was released pending a court hearing under New Jersey's 2017 bail reform law.
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