41. The non-transitory computer-readable medium of claim 39 , wherein the stored processor-executable instructions are configured to cause the processor to perform operations further comprising: determining a statistical envelope based upon received coordinates for each of the plurality of keys by calculating standard deviations about the calculated average coordinates for each of the plurality of keys; and saving the statistical envelope for each of the plurality of keys in the keypad layout data.
41. The non-transitory computer-readable medium of claim 39 , wherein the stored processor-executable instructions are configured to cause the processor to perform operations further comprising: determining a statistical envelope based upon received coordinates for each of the plurality of keys by calculating standard deviations about the calculated average coordinates for each of the plurality of keys; and saving the statistical envelope for each of the plurality of keys in the keypad layout data. 42. The non-transitory computer-readable medium of claim 41 , wherein the stored processor-executable instructions configured to cause the processor to generate an image of the virtual keypad using the keypad layout data using the keypad layout data cause the processor to perform operations further comprising: generating images of the plurality of keys in the virtual keypad in which a size of each key image is based upon the statistical envelope for each of the plurality of keys in the keypad layout data.