Whisper Integration package is offered by Elitesoft:

In light of the recent Whisper Upgrade to WhatsApp API message sending capability, and in response to interest indicated by several customers, Elitesoft is now offering a full package to customers that are new to Facebook/WhatsApp environment and Whisper setup with a full step-by-step walkthrough.

WhisperCRM adds WhatsApp API Capability:

WhisperCRM is now upgraded with the capability to send messages via WhatsApp API. Messages and its media content can be composed from Facebook Business home and linked to Whisper. All standard Whisper scheduling and Contacts management are also available with the new medium.