A method for unlocking a door for an authorized user of a vehicle via a door unlocking system of the vehicle includes providing a control at the vehicle, providing a near field communication device at the vehicle, and wirelessly communicating, via the near field communication device of the vehicle, with a near field communication-enabled smartphone when the smartphone is within a threshold distance from the vehicle. Responsive to the near field communication device of the vehicle communicating with the smartphone, it is determined whether or not the smartphone is an authorized device. The smartphone is authenticated as an authorized device for communication with the near field communication device of the equipped vehicle. Responsive to the smartphone being authenticated as an authorized device, the locking mechanism is actuated, at least in part via the control, to unlock the vehicle door for the user of the authorized device.