The Blending Buds have been used by pro makeup artists for years. They are used slightly damp, with liquid or cream foundation. To apply, you quickly tap the product all over your face, leaving no harsh lines, and perfect blending which helps hide any imperfections you may have.
The Blusher Brush is smaller, with shorter capras hair bristles. It allows you to tap, then buff in circles, with either liquid, cream, or powder, again with no harsh lines.
The Puff Brush, made of longer capras hair, and is best for loose or compressed powder. Load the brush, then begin buffing the powder onto your skin, in light, circular motions. While some do use this for liquid foundation, it is not as effective as the other two methods above.