APPNAME : Strange enough, "Netscape" is the application name for both IE11, Chrome, Firefox, and Safari.
APPCODENAME : Do not rely on it! "Mozilla" is the application code name for both Chrome, Firefox, IE, Safari, and Opera.
PRODUCT : Do not rely on it! Most browsers returns "Gecko" as product name!
SCREEN : The screen.colorDepth property returns the number of bits used to display one color.
All modern computers use 24 bit or 32 bit hardware for color resolution:
24 bits = 16,777,216 different "True Colors"
32 bits = 4,294,967,296 different "Deep Colors"
Older computers used 16 bits: 65,536 different "High Colors" resolution.
Very old computers, and old cell phones used 8 bits: 256 different "VGA colors".