Colour is a very important feature of icons and user interfaces. It is used to convey important information, about the availability and/or status of an action or object. Colour can be also used to identify intuitively interface components with similar functionality and to make content hierarchy comprehensible. Since not all people perceive the colours in the same way, digital applications’ colour palettes should support all forms of colour perception, including colour related impairments.

• Avoid using only a colour code to convey information about an action or content, for example by adding specific shapes and fillings to elements with the same meaning.
• Use a discreet number of colours: follow the principle of minimalistic design reducing it to the minimum.
• When choosing the colour palette or icons’ colours, avoid using logotype colours.
• Colours have strong cultural implications and taking them into consideration, both as potential strengths and weaknesses, may result in a better market positioning. A possible reference can be found on the “Information is Beautiful” website, a must-know reference for web designers and visual artists.