gpick is described as 'A color picker and color scheme creation tool' and is an app in the Photos & Graphics category. There are more than 50 alternatives to gpick for a variety of platforms, including Windows, Mac, Online / Web-based, Linux and iPhone. The best alternative is Just Color Picker, which is free. Other great apps like gpick are gcolor2 (Free, Open Source), Instant Eyedropper (Free, Open Source), Sip (Paid) and ColorZilla (Free).
gcolor2 is a basic colourpicker utility that allows you to select any colour on your screen, and, well, grab it's colour. It also allows you to save the colour you create to a file, which shows up as a list in the application.
Instant Eyedropper is a free color detection tool for webmasters that will identify and automatically paste to the clipboard the HTML color code of any pixel on the screen with just a single mouse click.
The refreshingly simple color picker for developers that instantly samples and encodes any color on your screen. Just one quick click to savor the flavor and you're set! See what’s on special with Sip below.
Colorpicker is efficient through its interface. Every features are accessible from the toolbar and shortcuts. You have the possibility to choose any color thanks to the three RGB sliders (soon HSL, CMYK, ...)!