The Brave 4 action camera has a zoom function that allows you to digitally zoom in on your subject. Here are the steps for using the zoom function:

1. Power on the camera and enter either photo or video mode.
2. Press the "UP" button on the side of the camera to activate the zoom function.
3. Use the "UP" and "DOWN" buttons to zoom in and out, respectively. Each press of the button will increase or decrease the zoom level by a preset amount.
4. When you have reached your desired zoom level, press the "Shutter/Select" button to take a photo or start/stop recording a video.

Note that the Brave 4 does not have an optical zoom lens, only a digital zoom function. Digital zooms can degrade image quality, especially at higher levels of zoom, so use the feature judiciously.

Also, note that the zoom function is not available in all recording modes. The default setting is no zoom. The zoom function is available in Video and Burst Photo and Timer Photo Mode.