Pinch to Zoom. Would it be necessary to label or indicate interaction with image

As pinch to zoom is a standard gesture on all the major mobile operating system (Android, iOS, and even the lesser-used ones), there should be no need to label it.

1. What happens when you pinch to zoom?
2. How do you pinch zoom?

What happens when you pinch to zoom?

Pinch to zoom in on content:

In full screen mode, touch the video with two fingers. Move your fingers away from one another, while touching the video screen. Once you let go, the video will play at the new zoom level.

How do you pinch zoom?

Pinch-to-zoom refers to the multi-touch gesture that zooms in or out of the displayed content on a device with a touch screen. These devices include a smartphones and tablets. To use pinch-to-zoom, touch two fingers on the touch screen, and move them apart to zoom in, or together to zoom out.