11. The method of claim 6 wherein the textual output is produced by processing the set of combined observations employing at least one of a Hidden Markov model and a Viterbi decoder.
6. A method for mobile device text entry, comprising: generating a first set of observations based on a set of possible intended user inputs and a determined set of digitized coordinates associated with the set of possible intended user inputs obtained via a text input device, wherein the text input device is a touch screen display; generating a second set of observations based on user inputs obtained via an audio input device, wherein user inputs via the text input device and the audio input device are obtained concurrently; combining the first set of observations and the second set of observations to produce a set of combined observations; and producing a textual output by processing the set of combined observations, wherein the produced textual output includes a first predetermined character that is predicted based on (a) a substitute character received by the text input device, the substitute character is different from the first predetermined character, and (b) pronunciation of the first predetermined character received by the audio input device.