You can send customised broadcast messages to users, devices, user groups and device groups enrolled in Hexnode MDM. Navigate to Manage tab -> Users -> select Users -> Click on Actions -> Broadcast Message.
In case if you want to send Broadcast message to selected Devices, Navigate to Manage tab -> Devices-> select Devices-> Click on Actions -> Broadcast Message.
You can also send Broadcast messages to user groups by selecting the required User groups or device groups and perform a broadcast message action onto them.
You may refer this link to know more about Broadcast Message feature in Hexnode MDM.