Texting on Phone (© BBS United / Getty Images)Click to enlarge picture

Your smartphone can be used to track your fuel consumption, determine the amount of carbon dioxide your car is producing, find the cheapest fuel, and more.

Did you know that your smartphone can be a powerful weapon for good in the fight to save the environment? It can help you avoid traffic, use less fuel and even tell you when to take your car in for simple maintenance — all things that can reduce your carbon footprint. How, you ask?

A smartphone is basically a small computer that fits in the palm of your hand. Sure, it’ll allow you to make phone calls and check your e-mail — we all know that. You can also download snappy applications and Web doodads that are designed to help you save time and money and make driving a little greener. Here are 10 apps that environmentally conscious smartphone users shouldn’t be without.

[Note: We don’t promote cell phone use while behind the wheel of a car, so please set up these useful applications before you leave the curb. That’s enough preaching.]

GasBuddy
Going out of your way for gas that costs a few cents less might be more wasteful than it’s worth. (Especially if, as this app says, prices can vary as much as 20 percent within a few blocks.) That is, unless you know exactly where to find it in your neighborhood. GasBuddy keeps tabs on current fuel prices in your area. Price information is delivered in four ways: on GasBuddy.com, on mobile browsers at GasBuddyToGo.com, by text message and via a slick new iPhone app ($2.99). The iPhone app offers a few extra features such as an “on fumes” button, which identifies the nearest station, and a list of roadside assistance numbers for most car makes. www.gasbuddy.com

Ecorio
This is a free program written for smartphones that employ Google’s Android platform, the first of which is the G1 from T-Mobile. Ecorio tracks your personal travels and then, depending on your mode of transport, will calculate your carbon footprint. It can also recommend the most efficient routes (burning less fuel means fewer harmful emissions) by accessing Google Transit, and even integrates with Zimride — a Facebook car-pooling network — to locate ride shares. The creators of Ecorio plan to bring it to the iPhone and BlackBerry, but for now it’s Android-only. www.ecorio.org

greenMeter
We know that pedal-stomping sabotages our fuel efficiency, but details beyond that are scarce. greenMeter ($5.99) computes your vehicle's power and fuel use characteristics and helps you modify your driving style to increase efficiency, reduce fuel consumption and cost, and lower your environmental impact. It uses your iPhone’s accelerometer — the built-in mechanism that tells the iPhone when it’s being tilted or shaken — to monitor the G-forces incurred when you step on the gas. In real time, greenMeter’s graphs show the effects of acceleration, rolling resistance and aerodynamic drag on factors such as fuel economy, carbon emissions and cost per mile. As the most sensitive driving-efficiency application among those discussed here, it is fitting that greenMeter demands some input from you to operate correctly: You’ll have to know (or at least estimate) your car’s drag coefficient, weight and drivetrain loss, not to mention the atmospheric pressure and temperature. www.hunter.pairsite.com/greenmeter

Have you ever tried a smartphone application designed to help you be a better, more conscious driver? Did it work?

Gas Cubby
You know those blank pages at the back of your car’s manual for recording service visits, the ones you’ve never even dreamed of using? Well, Gas Cubby ($4.99), which is available only for the iPhone, might just make a fastidious note-taker out of you yet. This app tracks two things: fill-ups and maintenance. By entering the number of gallons per fill-up, the cost per gallon and the odometer reading before and after each fill-up, Gas Cubby plots mpg, cost per mile, miles per tank and more. You can also set clever service reminders for oil changes, tire rotations, tune-ups and the like — and if you’re busy, you can always hit “snooze.” It’ll even break the data down into color-coded graphs you can view on the iPhone’s screen. Records can be exported to Excel spreadsheets. www.appcubby.com

Click to enlarge picturePrimo Spot (© PrimoSpot, Inc)

Primo Spot maps when and where street parking will free up (currently available for New York City). Color-coded icons indicate how soon parking zones will become legal, and which ones are a “bad idea.”

Primo Spot
Weaving through traffic in search of a parking spot drains your gas tank and your patience. It also compounds traffic snarls. Primo Spot ($5.99) is a crystal ball that maps when and where street parking might free up in metropolitan areas. Information is currently available for New York City, with other cities following soon. It can be accessed via an iPhone or cell phone Web browser. Color-coded icons indicate how soon parking zones will become legal, and which ones are a “bad idea.” Tell Primo Spot once you’ve parked and the app will tag your location and warn you before the spot becomes illegal again (because there’s nothing green about taking a cab to the impound lot). Primo Spot even shows the location of bike racks with photos of each one, as well as rates and locations for paid garages. www.primospot.com

Carbon Diem
After struggling with the chore of tallying his carbon footprint trip by trip, London grad student Andreas Zachariah set about creating a mobile app that does it for him. Carbon Diem (price to be announced), which works with any BlackBerry, has yet to become publicly available. However, Zachariah says that by using the built-in GPS in his BlackBerry and identifying motion patterns, Carbon Diem can tell if he is walking, driving, flying or taking the train or bus. Based on this information, it creates a tally of carbon emissions. Zachariah says he hopes companies will be able to better aggregate the carbon footprint of their employees via networked mobile devices. www.carbondiem.com

CarCare
A well-maintained car is substantially more efficient than one that is just clunking along. CarCare ($2.99) for the iPhone can make maintenance and regular service more manageable.It allows you to track any type of service via your iPhone, and then lets you know when, for example, to change your oil, rotate your tires or even wax your car. The more you use it, the less you will need RepairPal, a free app that displays the estimated cost of fixing an array of automotive ailments. www.karlbecker.com/carcare or repairpal.com

Where
Where pulls together a number of helpful services into a bushel of widgets for finding the stuff you need. You can download it free to your BlackBerry, Helio or iPhone, as well as access it on the Web. In addition to serving information from GasBuddy, ShopLocal and Yelp, Where also displays the location of Zipcar stations around the city. www.where.com

Carticipate
Considering the number of social networking apps for the iPhone, it’s surprising we don’t see more geared toward ride sharing. Carticipate (free) is a shining example of the potential of mobile devices to make driving more efficient. It lets you enter your trips, browse where others are headed and view routes in Google Maps. Find someone headed your way and you can e-mail, text or call him or her from within the program and possibly bum a ride or get someone to ride with you. Coming soon will be a chat function via Indalo. Carticipate is available on the iPhone and on Facebook, with other platforms to be announced soon. www.carticipate.com

Have you ever tried a smartphone application designed to help you be a better, more conscious driver? Did it work?

Traffic.com
Not only do traffic jams pump out greenhouse gasses, recent research even suggests that sitting in traffic can raise the risk of heart attack. You can visit traffic.com (free) on the Web before heading out, or the very light and quick mobile version (mobi.traffic.com) via your cell phone’s browser. Search by city or customize it for your own commute to view traffic snags, scheduled construction, length of delay and average speed. www.traffic.com

Jacob Gordon is a freelance writer, a blogger for TreeHugger.com and a producer of TreeHugger Radio. He can be reached at jacob@treehugger.com.

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