Two people used cell phones’ technology to track down people who had allegedly victimized them.

In the first case, police said a 14-year-old boy left his phone at on a bench at a Pearl City school about 5 p.m. Monday.

When he went back and found it was gone, he told his mother, who tracked her son’s phone to a school gym via the phone’s GPS signal.

The mother confronted two boys, age 18 and 17, at the gym and recovered the phone from the older teen, police said.

Police arrested both teens on suspicion of felony theft; they were released pending investigation.

On Sunday, a 22-year-old man was arrested after agreeing to meet with the victim of a robbery to return a phone in exchange for money.

Police said the suspect had grabbed another 22-year-old man’s cell phone and a small amount of cash about 8:10 p.m. Saturday in Waikiki.

The next day, the victim sent a text message to his stolen phone offering to give the robber money in exchange for his phone.

The robber agreed to meet the victim about 2 p.m., at whih time officers arrested the man on suspicion of second-degree robbery.