Clear Standards Carbon Tracker enables you to manage your personal carbon footprint from commuting, vacations, or business trips. Use the iPhone GPS feature to determine the approximate distance of each leg of your trip, select the mode of transportation, and let Carbon Tracker calculate your carbon footprint. Set monthly maximum footprint goals, and play an important role in helping to reduce carbon emissions globally. Stay tuned for future releases with more features!

Sidenote: At the point of posting this program has been marked as beeing freely available without costs. As this program is hosted with the AppStore the status might change. Authors like to publish their programs for free for promotion purpose and then make it commercial. Also it could happen that the author decides to take the program down.

http://appshopper.com/lifestyle/carbon-tracker