What are the applications of scattering of light in daily life?

Answer 1

In everyday life I would say the most commonly experienced example is the coloured patterns you see when oil spreads on water. Another similar example is the coloured reflection you see from the objective lenses of binoculars. Both of these result from the interference of light reflected from two (almost) parallel surfaces separated by a distance comparable with the wavelength of light.

If you look through the fabric of an umbrella at a distant street light you will see a diffraction pattern consisting of an array of bright squares; this is also formed by interference.

Other examples include -

Newton's rings seen when a convex lens is placed on a piece of flat glass
The formation of a spectrum by a diffraction grating used in a spectroscope
Airy's disc seen when a star is viewed in an astronomical telescope
Coloured patterns seen when a sliver of mica or a piece of stressed plastic is viewed between crossed polarisers (sometimes also seen when a CD case reflects light from a clear blue sky at a particular angle).
etc

Answer 2

Tyndall effect