A device including a display screen for displaying m-words of data, a text entry device for entering data, a processor receiving data from the text entry device and causing it to be displayed on the display screen. Upon activation the processor initializes a precursor to a predefined value. The device further includes a non-volatile memory storing a dictionary containing a plurality of entries, each entry including an index, a candidate word, and a score. The processor selects a list of n-number of candidate words from the dictionary whose index matches the precursor, and causes m-number of candidate words from the list of candidate words to be displayed on the display screen. The processor causes the display to prompt the user to select one of the displayed candidate words or enter a desired word using the text entry device. Furthermore, a tech-mode for extending a word dictionary for word-based text input is provided.