> For the complete documentation index, see [llms.txt](https://doc.sysdevmobile.com/kalipso/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.sysdevmobile.com/kalipso/6.0/documentation/controls/events/app-notified.md).

# App Notified

This event is triggered by a call to the PostAppNotification() action, or by a Notification sent by an external library on Android that is being executed with [RunAPK](/kalipso/6.0/documentation/actions/group-others/run-apk.md)(),[ BarcodeConnect](/kalipso/6.0/documentation/actions/group-barcode/barcode-connect.md)() or [RFIDConnect](/kalipso/6.0/documentation/actions/group-rfid/rfid-connect.md)() actions.

The main use is when you have services running in the background that need to notify your App that something happened, they can use [PostAppNotification](/kalipso/6.0/documentation/actions/group-others/post-app-notification.md)() action to do so.

#### Event available on the following operating systems

<figure><img src="https://1102213384-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FM6Wz3tBjSWbCweZ8NltT%2Fuploads%2FlMCpECAOJ3xRYg3Vgnqu%2F05_Supported_OS_android_ios_windows.png?alt=media&amp;token=4de523e1-6e2c-4501-806e-d0dd94dcd34f" alt="OS Supported: Android, iOS, Win"><figcaption></figcaption></figure>