The boy was trying to dump her body in styrofoam boxes after selling the phone for $40.
A court in Ho Chi Minh City sentenced a teenager to 12 years in jail on Wednesday for killing his friend to steal her phone.
Nguyen Pham Quoc Binh, 16, was accused of murder and robbery eight months after his arrest.
Binh and his victim, 15, were in the same group of friends at school. Her name was not revealed.
The indictment said that Binh murdered the girl in the stairwell of an apartment block in January after she refused to hand over her phone and continued texting.
He responded by picking up a concrete block and smashing her in the head multiple times, killing her on the spot.
Binh then rolled her body in a piece of cloth and left it there, before going to sell the phone for VND900,000 ($40).
The next day, he returned to the building with two styrofoam boxes to hide the body.
A guard discovered the girl before the boxes were taken away by garbage collectors.
Prosecutors said the motive was cruel and that Binh had shown no remorse.
Binh’s parents said that he had his own cellphone and motorbike, and that he had never been a bad boy. – VNExpress