The Ho Chi Minh City police arrested two people for allegedly snatching phones from women tourists in separate robberies in District 1 on Tuesday.
Nguyen Van Dang, 17, was seized by a patrolling officer after chasing him around alleys off Pham Ngu Lao Street in the backpacker area that afternoon, police said.
The shoeshine boy had snatched an iPhone 6 from a Korean walking on the street.
The teenager told the police that he only pretended to shine shoes to case tourism hotspots and look for potential victims.
Hours earlier officers in the same district arrested Dang Trieu Phu, 23, who allegedly snatched a phone on Nguyen Hue Street.
Phu rode a motorbike up to his victim and grabbed the phone before speeding away.
A group of patrolling police officers chased after him and knocked him off his motorbike near the Notre-Dame Cathedral, one of the most famous tourist attractions in the city.
Phu has two previous convictions for robbery.
The cell phones were returned to their owners later.