Controlling Media Playback on a Smartphone: A person's hand interacting with a smartphone screen, which displays a user interface that appears to be designed for controlling audio or video playback. The UI is dark-colored and features various buttons and sliders, some of which are highlighted in green. A large circular dial dominates the center of the screen, surrounded by several smaller controls. In the background, out-of-focus lights can be seen, suggesting that the person is likely using their phone outdoors at night or in a dimly lit environment.