The stalled iPhone application from the Cambridge, Massachusetts-based car-sharing service Zipcar has finally made its way to the App Store! The app gives the car rental service the unique facility of allowing its members to locate and reserve a Zipcar rental vehicle, unlock it with the iPhone touch-screen, and drive it off the parking lot!

Zipcar - which rents its vehicles, parked in central locations, on hourly basis to its members – has further enhanced its rental service with the help of the newly-released app.

After a convenient online reservation of a car from Zipcar, the members can to go straight to the chosen vehicle and easily unlock it by tapping the RFID-enabled membership card to a windshield sensor.

Talking about the app, Zipcar's chief technology officer Luke Schneider said: “The iPhone is a pipeline for almost one-third of our members. This is something they have been asking for.”

To avail the car rental service at Zipcar - which is operational in 13 major US cities and 120 university campuses – members have to pay a $50 yearly charge, along with the nearly $7 per hour rental fee for the car, including gas and insurance.

Saying that the Zipcar app is clearly a “breakthrough,” David Cole, chairman of the Center for Auto Research, noted that it is the first app to control the operation of a car with the Apple iPhone!