The 26-year-old woman had been walking in the 1600 block of Post Street near Laguna Street at about 11:05 p.m. when the four suspects -- described as black males between 18 and 25 years old -- approached her, police said.
One of the suspects produced a stun gun and used it on the woman, who then fell. One of the suspects took her phone, and the men ran away, police said.
Officers tracked the phone and arrested one person who was allegedly in possession of the stolen cellphone.
Police said the woman was not injured in the attack.