free2go for car2go
Update (March 2018): As the underlying API stopped working, we discontinued the free2go service after five and a half years and removed the apps from the Play Store/App Store.
Short Description: This app helps identify nearby car2go with low fuel that are eligible for 20 minutes of free driving credit. Just stop at a gas station at any time during your trip and re-fuel using the credit card supplied in the car.
Looking for a way on how to use car2go for free?
Available for iOS and Android.
Screenshots: