It is not only not permitted to use the mobile phone while driving, but it is as well very risky. You endanger yourself and others. The legal - and much more comfortable - solution is to use a hands-free-kit, which is simply fastened to the headrest.
Use the mobile in the car? Of course!
Very comfortable and a little bit futuristic is the hands-free kit on the headrest. Within five minutes you are able to send and receive.