When a driver accepts a pickup or delivery order in the Driver app you can set it so that the customer will be notified that the driver is on the way and will be there soon.
To Enable Notifications
Go to Settings > Admin > Notifications > General Settings page in CleanCloud
Enable the Driver On Their Way Notifications, Email, Push or SMS notification option
Press the Update button below
If you have the driver location option enabled it will also send them a link to view the driver's location.