A green color scheme in app design typically refers to the use of green hues as the primary colors in the application's interface. This can include shades of green for text, buttons, and backgrounds. The choice of green can be for aesthetic reasons, to convey a sense of nature or freshness, or to follow a branding guideline. Green is often associated with growth, health, and eco-friendliness. In user interface design, color schemes play a crucial role in user experience and accessibility.