It is interesting to think about how web-based applications could be used to help us all make more climate-friendly decisions. In Canada, developers competed for $40,000 in prizes in a contest called “Apps4Climate Action” to see what creative ideas folks could come up with. Some of the winners included a web-based app that will figure out when you should water your lawn. Another group developed a mobile app that enables students to track the amount of carbon dioxide they generate by recording everything from hot water use and eating, to transportation and "entertainment behaviors." Check out all the innovative apps that were submitted.

What sort of app would you design or find useful?