A nudge is a feature that will send a reminder to anyone receiving a broadcast who hasn't opened or acknowledged the notification. This is a handy tool that can help the recipients of the broadcast to stay engaged.
Don't know what Broadcasts are? Please read the Broadcast Overview documentation.
Step 1: Delivery Settings
You can access the nudge option only when you reach the 'Delivery settings' page.
When sending broadcasts there are 3 key steps
Step 2: Nudge
Towards the bottom of the page, you will see the option to enable a nudge. You can also enable how long after the initial broadcast you would like the recipients to receive the nudge if they fail to respond.