Eric Gay, 43, is believed to be responsible for at least five robberies and is being questioned in a total of eight incidents, all but one on the subway, between November 17 and November 20.
The break apparently came after one victim was robbed on the F train at the Avenue U station in Sheepshead Bay.
Detectives responded and used the Google app on the victim's phone, then canvassing the area with the victim. They reportedly spotted the suspect, and the victim confirmed his identity.
Police took Gay into custody.
Detectives found a MetroCard that belonged to one of the other victims in his possession. Authorities say he simulated a firearm during the robberies and asked for money and phones.
None of the victims actually saw a weapon.
Police also had video of the suspect, who struck in the West and East Villages of Manhattan and Fort Greene in Brooklyn.
