With the OneSignal integration, you can create and send OneSignal push notifications using workflows, view push notifications on contacts' activity timelines, and segment users based on engagement with push notifications.
By OneSignal external_user_id: users will need to select the HubSpot contact property they want to match with the external_user_id in OneSignal. To do so:
In your HubSpot account, click the Marketplace iconmarketplace in the main navigation bar. Under Manage, select Connected apps.
Click Contact Matching.
From the dropdown menu, select the HubSpot contact property you want to use for matching with the OneSignal external_user_id property. This matching option is available for both the Send OneSignal notifications and Edit OneSignal tags workflow actions.
Automate OneSignal push notifications
You can automate sending OneSignal push notifications using workflows.
In your HubSpot account, navigate to Automation > Workflows.
In the top right, click Create workflow.
In the left panel, select Contact-based and click Next in the top right.