greenMeter is an app that connects with one’s vehicle and is able to monitor the power and fuel usage characteristics.
Through real-time analysis and (dashboard-style) feedback, this app helps to evaluate the user’s driving activities and provides insights on reducing fuel consumption as well as cost. It claims to help each driver save hundreds of dollars yearly on fuel expenses, and estimates that about 2 million gallons of gas can be save and 47,000 tons of CO2 emission is reduced. The app is only available on iOS.