The initial cost to introduce the devices nationwide is $4.3 million, followed by operating costs of $159 million during the next 12 years.
Mr Horne said it would provide a number of flow-on benefits for the community.
"For example, it will reduce the time it takes our staff to carry out a large number of routine tasks, which means they will get through more work in less time."
Mr Horne said it would also reduce congestion on the police radio, where many routine queries could now be handled using the mobile devices.
Rotorua MP Todd McClay said introducing the devices would mean Rotorua police could focus more time on preventing and tackling crime on the ground.
"An 11-month trial last year involving over 100 officers in four police districts showed that these mobile devices allow each officer to spend, on average, an extra 30 minutes per shift on the frontline," Mr McClay said.
"They can access, input and share important information immediately, without having to travel back to their station to access databases or write reports."
All the devices will be password protected and can be tracked, locked or wiped if they are lost or stolen.