---
title: "Light"
canonical_url: https://developer.repebble.com/docs/c/User_Interface/Light/
last_updated: 2026-10-29
sdk_version: 4.33.1
---
# Light

Source: https://developer.repebble.com/docs/c/User_Interface/Light/

Controlling Pebble's backlight

The Light API provides you with functions to turn on Pebble’s backlight or put it back into automatic control. You can trigger the backlight and schedule a timer to automatically disable the backlight after a short delay, which is the preferred method of interacting with the backlight.

## Function Documentation

void light\_enable\_interaction(void)

Trigger the backlight and schedule a timer to automatically disable the backlight after a short delay. This is the preferred method of interacting with the backlight.

void light\_enable(bool enable)

Turn the watch's backlight on or put it back into automatic control. Developers should take care when calling this function, keeping Pebble's backlight on for long periods of time will rapidly deplete the battery.

#### Parameters
 enable

Turn the backlight on if `true`, otherwise `false` to put it back into automatic control.

bool light\_is\_on(void)

#### Returns

true if the backlight is currently on in any form (on, timed, or fading out). Returns false only when the backlight is fully off. Useful for apps that want to behave differently depending on whether the screen is currently lit — e.g. skipping an animation or queuing a visual cue for when the screen wakes.

void light\_set\_color(GColor color)

Tint the backlight LED to the given color. The color persists while the app is foregrounded and is automatically reset to the user's default (white) when the app exits or is preempted by a system notification. On platforms without a color backlight this is a no-op.

##### Note

GColor carries only 2 bits per channel (64 distinct tints). Use [light\_set\_color\_rgb888()](https://developer.repebble.com/docs/c/User_Interface/Light.md#light_set_color_rgb888) if you need the full 8-bit-per-channel range that the LED hardware supports.

#### Parameters
 color

The color to tint the backlight to.

void light\_set\_color\_rgb888([uint32\_t](https://developer.repebble.com/docs/c/Standard_C.md#uint32_t) rgb)

Tint the backlight LED to a packed 24-bit RGB value (0x00RRGGBB). Same persistence semantics as [light\_set\_color()](https://developer.repebble.com/docs/c/User_Interface/Light.md#light_set_color): the override lasts while the app is foregrounded and is reset on app exit or system preempt. No-op on platforms without a color backlight.

#### Parameters
 rgb

Packed 0x00RRGGBB value; 8 bits per channel. High byte ignored.

void light\_set\_system\_color(void)

Restore the backlight to the user's default color. Rarely needed — the system resets automatically on app exit. No-op on platforms without a color backlight.