---
title: Life cycles
framework: watchkit
role: collectionGroup
path: watchkit/life-cycles
---

# Life cycles

Receive and respond to life-cycle notifications.

## Overview

Overview The system reports changes in your app’s execution state to your SwiftUI environment and your extension delegate object. State changes correspond to major events in the lifetime of your app, such as the app launching or moving into the background. Use the state changes to trigger relevant tasks, such as loading shared resources and configuring your initial user interface. The table below shows the possible states and their implications for your app.  |   |   |   |   |   |  For more information, see Handling Common State Transitions. Receive background information When the system receives background data, it may not immediately wake the watchOS app to process that data. Instead, it may delay delivery of the data to preserve battery life. If the app is currently running—either active and onscreen, or inactive and the frontmost app—the system immediately delivers the data to the app. If the app is in the background, the system wakes the app within 10 minutes to deliver the data.

## Topics

### Responding to life cycle events

- [Handling Common State Transitions](watchkit/handling-common-state-transitions.md)
- [Working with the watchOS app life cycle](watchkit/working-with-the-watchos-app-life-cycle.md)
- [Handling User Activity](watchkit/handling-user-activity.md)
- [Taking advantage of frontmost app state](watchkit/taking-advantage-of-frontmost-app-state.md)

## See Also

### Runtime management

- [Background execution](watchkit/background-execution.md)
- [Using extended runtime sessions](watchkit/using-extended-runtime-sessions.md)
- [WKExtendedRuntimeSession](watchkit/wkextendedruntimesession.md)
- [Interacting with Bluetooth peripherals during background app refresh](watchkit/interacting-with-bluetooth-peripherals-during-background-app-refresh.md)