Not only can you find any public charging and alt-fuel station from a user-friendly source, you can also view it on your iPhone and iPad. The US Department of Energy (DOE) has launched a new mobile app so drivers can find any green fuel you can think of – biodiesel (B20), electricity, ethanol (E85), hydrogen, natural gas and propane – at nearly 12,750 stations in the US.

The free iOS app for the Alternative Fueling Station Locator website displays fueling station addresses, phone numbers, and hours of operation in the vicinity of the driver. They can also set parameters for the search such as what payment methods are accepted.

We poked around with it a bit and found that the clear popularity winner is electric vehicle charging stations – with 6,699 public stations shown on the map. Liquefied petroleum gas (propane) is number two, at 2,705 stations. The bottom two on the chart are liquefied natural gas (42) and hydrogen (10).

The DOE has been big on apps lately. Earlier this year, the agency announced winners of its Apps for Vehicles Challenge aimed at improving safety, fuel economy and driver comfort. The contest brought in almost 40 entries, and judges gave their prize to the Dash app; the popular choice went to the MyCarma and Green Button Gamer took the safety innovation prize. Fuel Economy Coach won the fuel efficiency motivation award. That app gives drivers feedback and coaching that's supposed to help them cruise more efficiently. It does require a hand-free device, though, to alleviate distracted driving.