Live Zoom is available when using the Videos app for playback. It allows you to zoom in or zoom out on a portion of a video while it’s being played to make the desired section appear larger or smaller.
While viewing a video, use your index finger and thumb in a pinching or spreading motion on the touchscreen to zoom in or out.
You don't need to press too hard; the touchscreen is sensitive enough to pick up a light, but firm touch.