Ecorio, developed by five University of Waterloo students, helps mobile users keep track of - and share ideas for reducing - their carbon footprint. (Ecorio)

A group of Canadian engineering students has won a $275,000 US prize from internet search giant Google Inc. for a mobile phone application that lets users calculate and adjust their travel carbon footprint.

The group of five students was among ten groups named winners of the top prize of Google's Android Developer Challenge, which asked developers to come up with useful applications using Google's software platform.

Their program, Ecorio, gives users the ability to reduce their environmental footprint with tools that provide transit options for trips, allow them to invest in carbon reduction projects and share their tips with other users.

The Ecorio team comprises recent Waterloo engineering graduates Jeff Kao, Robert Lam, Taneem Talukdar and University of Toronto masters candidates Gary Pong and Jason Wong, who describe themselves on their website as five guys from Ontario who " think that this environmental thing might be for real."

"There are many people with lots of ideas on how we can live smarter, greener and sustainable lives. Ecorio is one piece of that mosaic," they write.

Other applications that won top awards from Google included programs that help users find taxi cabs, scan product barcodes and personalize photos.

Google released Android, a free downloadable software development kit for mobile phones, in November 2007, with the goal of creating a common platform that would make it easier for developers to create programs and for consumers to surf the web on cellphones.

They launched the contest at the same time, promising to give more than $10 million in prizes.

The move was also seen as Google's first move to expand the reach of its search tools to mobile handsets.