Downloading ColorDial 1.6 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. The actual developer of this free software for Mac is Norganna's AddOns Pty Ltd. ColorDial for Mac belongs to Design & Photo Tools.
From the developer:
ColorDial is a rich and powerful, open source color wheel/picker for OS X. ColorDial sports a magnified reticule for picking the exact color you want with the eyedropper tool, colored sliders to help you fine tune your perfect tint and hue, a color wheel to find your complementary color shemes and the ability to copy CSS ready definitions when you're done.
You may want to check out more Mac applications, such as Vectorworks 2010 Viewer, Polaris or Send Photo Pro by ZoomFoot, which might be similar to ColorDial.