---
title: "Wakeups"
canonical_url: https://developer.repebble.com/guides/alloy/wakeups/
last_updated: 2026-06-24
sdk_version: 4.43
---
# Wakeups

Source: https://developer.repebble.com/guides/alloy/wakeups/

Wakeups let your Alloy app schedule itself to launch at a future time, even if it isn't running. When the wakeup fires, the system launches your app and you can read the wakeup details to know why it was started.

> **Platform Support** : Wakeups are available on Emery (Pebble Time 2) and Gabbro (Pebble Round 2).

## Scheduling a Wakeup

Import the `WakeUp` class and call `schedule()` with a timestamp (in milliseconds, as returned by `Date.now()`), a numeric `cookie` of your choice, and whether the user should be notified if the wakeup is missed:

```
import WakeUp from "pebble/wakeup";// Fire 3 seconds from nowconst id = WakeUp.schedule(Date.now() + 3000, 12345678, false);console.log(`Scheduled WakeUp id ${id}`);
```

`schedule()` returns an `id` you can later use to query or cancel the wakeup. Persist the `id` (for example with `localStorage`) if you need it across launches.

## Methods

| Method | Description |
| --- | --- |
| `WakeUp.schedule(time, cookie, notifyIfMissed)` | Schedule a wakeup at `time` (ms). `cookie` is a number passed back to your app. `notifyIfMissed` shows a missed-event notification if the wakeup couldn't fire. Returns an `id`. |
| `WakeUp.cancel(id)` | Cancel a previously scheduled wakeup. |
| `WakeUp.query(id)` | Return a `{ time, scheduled }` object describing the wakeup - `time` is the scheduled time in ms and `scheduled` is `true` if it is still pending - or a falsy value if it no longer exists. |

## Detecting a Wakeup Launch

When your app is launched by a wakeup, `watch.wake` is set and contains the wakeup's `id` and `cookie`:

```
console.log(`Launch reason ${watch.launch.reason}, arguments ${watch.launch.arguments}`);if (watch.wake) {console.log(`Launched by wakeup id ${watch.wake.id}, cookie ${watch.wake.cookie}`);}
```

## Receiving a Wakeup While Running

If a wakeup fires while your app is already running, it is delivered as a `"wakeup"` event on `watch`:

```
watch.addEventListener("wakeup", wake =\> {console.log(`wakeup id ${wake.id} occurred while running`);WakeUp.cancel(wake.id);});
```

## Managing Stored Wakeups

Because a wakeup `id` outlives a single launch, it's good practice to validate a stored `id` on startup and discard it if the wakeup is gone or stale:

```
const id = localStorage.getItem("wakeid");if (id) {const wakeup = WakeUp.query(id);if (!wakeup) {// The wakeup no longer existslocalStorage.removeItem("wakeid");} else if (wakeup.time \< Date.now()) {// The wakeup is in the past; cancel itWakeUp.cancel(id);localStorage.removeItem("wakeid");}}
```

See the [`hellowakeup` example](https://github.com/Moddable-OpenSource/pebble-examples/tree/main/hellowakeup) for a complete project.