In material design, apps are responsive to user input:
- Touch, voice, mouse, and keyboard are all equally important input methods.
- UI elements appear tangible, even though they are behind a layer of glass (the device screen). To bridge that gap, visual and motion cues acknowledge input immediately and animate in ways that look and feel like direct manipulation.
Responsive interaction elevates an app from an information-delivery service to an experience that communicates using multiple visual and tactile responses.