NeoCal for Pocket PC User Guide
NeoCal contains built-in themes that can be selected to alter the overall appearance of the main display and keyboard. Themes do not affect the operation of NeoCal in any way, but selecting a theme that is visually appealing can increase your efficiency when using NeoCal.
Generally, a theme specifies most of the visual aspects of the calculator including colors, margins, spacings, display lines, font size, border type, and dynamic keyboard settings. Some of these characteristics can be specified or overridden in the Preferences dialog to further customize your interaction with NeoCal.