There's a new way to keep track of the hundreds of runners in tomorrow's Scotiabank Calgary Marathon.

A group of tech-savvy volunteers created a smart phone app to tell you where your friends are along the course.

Ben Reed helped design the Zyris Marathon Tracker.

"They'd be able to download the application for free, load it on their phone and it runs in the background as a service that is able to kind of access the GPS data of the runner’s phone."

All the runner has to do is have the phone on them, said Reed. The phone sends updates every two minutes.

"We don't need any physical infrastructure to make it happen," said Reed.

"Via the cell phone or the GPS network that exists, we're just able to use that to get the information back to our servers and then we just display that on the webpage."

The app is available for Android phones.

Armchair spectators can log on to a website at home to see the updates.

The marathon gets underway tomorrow at 7 a.m. MT and will mean dozens of road closures for drivers.