Using Chat SDK for Android, you can send notification messages to your user's device when the device is either idle or running the client app in the background. For group channels, notifications can be configured to display an alert, play a sound, or place a badge on the client app's icon.

Push notifications for Android client apps are sent using Firebase Cloud Messaging (FCM) or Huawei Mobile Service (HMS) which contains custom data that your app needs in order to respond to the notifications. When a message is sent to the Sendbird server through our Chat SDK, the server communicates with FCM or HMS which then delivers a push notification to an Android device where the client app is installed.

By default, when a user's device is disconnected from the Sendbird server, the server sends push notification requests to FCM for the messages. The Chat SDK automatically detects when a user's client app goes into the background from the foreground, and updates the user's connection status to disconnected. Therefore, under normal circumstances, there is no need to explicitly call the disconnect() method.

Push notifications support both single and multi-device users and they are delivered only when a user is fully offline from all of their devices. In other words, if a user is online on one or more devices, notifications aren't delivered and thus not displayed on any device.

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Push notifications with multi-device support provide the same features as our general push notifications, but with additional support for multi-device users. When implemented, notifications are delivered to all online and offline devices of a multi-device user but through our Chat SDK, push notifications are displayed only on offline devices and ignored by online devices. As a result, client apps are able to display push notifications on all offline devices, regardless of whether there are one or more online devices.

For example, let’s say a multi-device user who has six devices with your client app installed is online on one of the devices and offline on the remaining five. When general push notifications are implemented, notifications aren’t delivered to any of their devices. But when push notifications with multi-device support are implemented, notifications are delivered to all six devices and displayed on the five offline devices.

By default, when a user's device is disconnected from the Sendbird server, the server sends push notification requests to FCM for the messages. The Chat SDK automatically detects when a user's client app goes into the background from the foreground, and updates the user's connection status to disconnected. Therefore, under normal circumstances, there is no need to call the disconnect() method.

To find out which type of push notification best fits your use case, see the following table.

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Users can set their preferences for receiving notifications in their devices. The following is a list of functionalities that our Chat SDK provides.