A modular device includes base and color sensing portions. The color sensing portion has a face, a controlled light source having a first channel between the light source and the face, and a color sensor arranged at a distal end of a second channel. The color sensor receives light reflected from the target surface and generates output signals representative of a surface color. The first and second channels extend at least 45 degrees apart from each other and respective to the face. The base portion communicates with the color sensor and a user interface enabling control input for the color sensor. The program further receives the output signals from the color sensing device and displays a first image of the detected color, and displays a second image of a user-selected color beside the first image. Color data values are further displayed corresponding to the difference between displayed colors.