Eco-geeks will love these top 5 iPhone applications via Earth2Tech that will help you save money on gas AND help reduce your carbon footprint by using less fuel:

1) AccuFuel: This nifty app lets you track your gas mileage with the help of fancy graphics and a quick performance comparison. Made by Appigo. 99 cents.

2) FuelGage: Doesn’t have the sparkly graphics that AccuFuel has, but offers the same utility. Track multiple trip totals for one or more vehicles, and even figure out how to split the gas bill. Made by Joseph Kueser. 99 cents.

3) GasHog: No frills, no graphs, but offers the same functionality as the two programs above. 99 cents

4) CarStat: Again, not a lot of pomp and circumstance, but this program does allow you to track fuel costs for multiple vehicles – for one additional dollar. Made by Stephen Blessing. $1.99.

5) WHERE: Works with GPS and GasBuddy to find out gas prices at the nearest stations. Made by uLocate Communicate, and free of charge.

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