Mr Betchitti said the message to those drivers was they might think they got away with it, but being stopped by police could have saved someone's life.
"It was frustrating because we can't have staff everywhere," he said.
Mr Betchitti said seeing 12 people on their phones during just 60 minutes showed there was still a "significant problem" in Rotorua.
"It is still a problem. It is such an in-cab distraction. There have been a number of significant crashes in and around Rotorua where the use of cell phones have been proven to be a factor."
Fellow road policing unit Sergeant Chris McLeod said drivers being distracted by mobile phones was happening "more so than ever".
He said drivers took notice of the law change in 2010 but were now "blase".
"I would say it's more prevalent now. We've definitely gone backwards."
He said police officers found it relatively easy to spot drivers using their phones while driving.
"They slow down a bit thinking they are doing something really clever but then they start to wander across the centre line. They drive into parked cars and crash into cars straight ahead of them."
Mr McLeod said he had some simple advice.
"Turn the phone off when you're driving. For a lot of people that's not possible so if your phone rings or you need to send a text, pull over. You're only stopped for 10 to 15 seconds and you're out of harm's way. You will never forgive yourself if you run someone over or crash into someone more vulnerable than you."
Meanwhile, Mr Betchitti said the police sting, which was one of several carried out by the road policing unit from time to time, also resulted in six infringements being issued for incorrect use of or failure to use safety belts.
That included one for a 6-year-old in the front seat of a vehicle with just a seat belt and not in an approved child restraint.
Undercover sting:
* 2 tickets issued for drivers using their phones
* 10 other drivers spotted but not able to be stopped
* Using your phone while driving incurs a fine of $80 and 20 demerit points
* Using mobile phones while driving became illegal in 2010