iOS Notification Grouping

In iOS 12 and newer, Apple supports grouping notifications with specific "thread ids" along with adding a summary and how many notifications are within that summary.

These parameters can be set directly into the notification payload from the OneSignal API using the thread_id, summary_arg, and summary_arg_count parameters.

Android Notification Grouping

Simply enter any value in the “Group Key” field under the Android Options when Sending Push Messages. This is the android_group parameter on the REST API. Notifications with the same group key will automatically group on the device.

📘

Android 7+ Default behavior

• Automatically groups your notifications after the device has 4 or more visible notifications for your app, even if you don't set a group key.
• Automatically generates the text for the summary notification for the grouped notifications.
  The custom group message only shows on Android 6.0 (Marshmallow) devices and older.

The above will cover most common notification grouping cases and is the recommend path. If you need more customizations see the Android NotificationExtenderService to group messages and add another NotificationExtenderService to update the summary notification. See Android's Group Notify Guide for more details.

Note there are some limitations that Android 7+ has for these summary notifications. You can only modify the text, accent color and small icon (not large icon). However, you can still modify the children.

• Also works on Amazon devices, set the group key listed under the amazon settings as well.