1. A mobile wireless communications device, comprising: a housing; a transceiver carried by the housing for transmitting and receiving radio frequency (RF) signals carrying communications data of speech; a processor coupled to the transceiver for processing the communications data as speech that is transmitted and received to and from the transceiver; a keyboard and display carried by the housing and connected to the processor; a speech-to-text and text-to-speech module for converting communications data as speech received from the transceiver to text that is displayed on the display and converting text that is typed by a user at the keyboard into communications data as speech to be transmitted from the transceiver on an RE signal.