It was just a matter of time. The NTT Docomo, Nissan Motor Co., Ltd., and Sharp Corporation have jointly developed a cellphone that can be used as a car key.   The new mobile gadget is expected to have the usual remote functionalities like locking and unlocking car doors and even starting the car. After unveiling the devices at ...

Simple answer:  No.  At least not at the moment.  I suppose over time, this can be a reality. And here's why:  For modern cars using key-less systems to open the car, the “car key” does its job by sending radio wave signals to a receiver inside your car. Once received and acknowledged as the right signal frequency, the door ...