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

# Overlay: a line of text and a countdown on every phone

> Overlay puts a short line, with an optional countdown, across the top of every guest's phone whatever mode is playing, until you take it off or it reaches zero.

An overlay is a short line that shows across the top of every phone in the show, whatever mode is playing. Use it for "Show starts in", "Short break, back soon" or "Last call at the bar", with a countdown if you like.

<video autoPlay muted loop playsInline src="https://media.luce.show/docs/v1/modes/overlay-on-air-light.mp4" aria-label="Putting an overlay on air: the phones panel shows Show starts in with a five-minute countdown, then the overlay is replaced by another" />

## Prepare overlays

Keep up to 12 overlays ready. Each has:

* **Text**, up to 60 characters.
* **Countdown**: none, **Until a time** on the event's clock, or **For a while**, a number of minutes from the moment it goes on air. At zero the overlay comes down by itself.

![Overlay mode with the On the phones panel and a list of four overlays, each with a Put on air button](https://docs.luce.show/docs/images/modes/overlay-light.png)

## Put one on air

Choose **Put on air** next to an overlay. One overlay is on air at a time: a new one takes the place of the last. Choose **Take off** to remove it. Saving changes to an overlay that is on air changes it on every phone.

> [!NOTE]
>
> Overlays go on air once the event is published.


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