For agents
Open GenieCRM™ and allow notifications when the browser asks. That is the whole setup. On a phone, add GenieCRM™ to the home screen first, then allow notifications.
For clients
Registered portal clients are asked once, in their own portal, and can decline without losing anything else.
What it costs
Nothing. There is no per-notification charge and no third-party notification vendor involved — the delivery runs on the browser makers’ own free services.