The 51-year-old victim, who the New York Post identified as an editor for the site Brownstoner, was aboard a Manhattan-bound train in the Nostrand Avenue station when the suspect punched her in the face repeatedly before slashing the left side of the face with a sharp object about 5:45 p.m., NYPD officials said.
He then grabbed her iPhone and fled, police said.
She was treated at Kings County Hospital and initially listed in stable condition, police said.
The suspect, whose name wasn't immediately released, was on the run until Monday when police caught him in Newark, an NYPD spokeswoman said Tuesday afternoon.
He was still awaiting formal charges Tuesday afternoon, police said.
It wasn't immediately clear what led to his arrest.