> ## Documentation Index
> Fetch the complete documentation index at: https://c5tako.ziphers.space/llms.txt
> Use this file to discover all available pages before exploring further.

# APP

> Use the built-in Buzzer and Flashlight.

Use the Buzzer for sound and the display as a light source.

## 🔊 Buzzer

```text theme={"theme":{"light":"github-light","dark":"dracula"}}
APP → Buzzer
```

| Menu         | Purpose                              |
| ------------ | ------------------------------------ |
| `Play Music` | Play a bundled sample tune.          |
| `Play Note`  | Play the selected note or frequency. |

<Steps>
  <Step title="Choose a sound type">
    Open `APP → Buzzer`, then select `Play Music` or `Play Note`.
  </Step>

  <Step title="Choose a sound">
    Use up/down to move through the list, then press the center button to play it.
  </Step>

  <Step title="Stop sound">
    Press the center button to stop playback. Wait for playback to stop, then press left to go back. If the display does not respond, use [the feature-stop procedure](/en/getting-started/controls#stop-an-active-feature).
  </Step>
</Steps>

<Info>
  🎬 **Media to add:** A Buzzer clip showing “Choose Play Music → play → stop → choose Play Note”; keep the clip volume at a safe level.
</Info>

## 🔦 Flashlight

```text theme={"theme":{"light":"github-light","dark":"dracula"}}
APP → Flashlight
```

Use the screen as a light source. Follow the hint at the bottom of the display to turn it on, change its color, or turn it off. To exit, use [the feature-stop procedure](/en/getting-started/controls#stop-an-active-feature).

<Info>
  🎬 **Media to add:** A Flashlight clip showing on, color change, off, and holding the center button to exit.
</Info>

<Tip>
  The Flashlight uses light from the display. It is suitable for close-range illumination, not as a high-power torch.
</Tip>