Police say the robberies, which took place between June 29 and September 7, each involved either a lone suspect or two or three of the suspects working together.
In three of the robberies in Brooklyn and one of the robberies in Queens, police say a male suspect walked into a Metro PCS store, showed a gun and demanded money before taking off with an unknown amount of cash.
One of the robberies of a Metro PCS in Brooklyn involved a woman, who also walked in with a gun and made off with cash.
Three of the robberies at Metro PCS stores in Brooklyn and one in Queens involved two men, police said. In those, they suspects walked in, showed a gun and took off with cash.
In another Metro PCS robbery in Queens, police say all three suspects, two men and a woman, walked into the store with a gun and got away with unknown amount of money.
Police say no one was injured in any of the robberies.
If you have information, call police or Crime Stoppers at 1-800-577-TIPS (8477) or visit www.nypdcrimestoppers.com.