EnLighten counts down the seconds until the green light, and chimes a warning so you're ready to go as soon as the traffic lights switch from red to green.
Sean Lewis, team leader of real-time operations at Christchurch Transport Operations Centre (CTOC), said he had been looking for something to help ease the city's congestion woes since the earthquakes.
He had even approached a software designer to create something similar, when he came across Connected Signals, the US company which developed EnLighten.
"There's a lot of lost opportunity due to inefficiency at intersections. Basically the light goes green and people are sitting there staring out the window or occupied with other activities and miss the fact that the light's turned green," he said.
"It happens a lot more than you think ... we see it all the time. Every time the light turns green there's a lag, sometimes of four to five seconds, and that's enough time to get two or three cars through, so from our point of view we're quite keen on the efficiency benefits that come about from it.
"It would give drivers "better context of the wait times", he said, and would also show how little time they would have saved by running a red light.
The CTOC had seen an increase in red light running and inattention since the earthquakes, Mr Lewis said.
"Whether that's because people are driving different routes, whether that's because the landscape around them is changing every day when they do their journey, we're seeing less attention when the lights turn green," he said.
"So it's something that has been bugging me for quiet a while."
Working with Connected Signals had been a "win-win" situation, Mr Lewis said - with Christchurch getting the benefit of the new technology at no cost to the taxpayer or ratepayer, and Connected Signals gaining experience in developing a system for use in countries that drive on the left-hand side of the road, as well as one that works with the traffic control system used by the majority of New Zealand and Australian cities, but very few in the US.
The company trialled the technology on Christchurch's dummy traffic management system, before being allowed access to the real thing, Mr Lewis said, to ensure security was not compromised.
The system was now live and available to download, with versions compatible with both iOS and Android devices.
Only a handful of people were currently using the programme, Mr Lewis said - some signals engineers and some of Mr Lewis' family and friends.
"The family and friends think it's great. The signal engineers say, 'hhmm I [already] know what the wait time is before I arrive at this intersection'," he laughed.
The user interface was "very well developed", Mr Lewis said, with safety in mind.
The screen will only display the countdown if the phone is vertical, with the idea being that it's placed in a mounted window bracket - a feature that was devised by the Christchurch end.
"The biggest thing is you have to use it in a legal, safest possible manner," he said.
"So you have to put it in a window bracket and you have to start the app when you hop in the car, you can't decide halfway there, 'oh this light's been red for a long time, how do I turn this thing on?', because that's just not legal.
"The key message there is it has to be used safely. We've got some safeguards in there to try to force you to use it properly, but at the same time it's like anything else, you have to follow the rules."
