WhatsApp for Business is a special WhatsApp Messenger app for small business users which let them offer customer service to regular WhatsApp users using a verified profile and special analytics tools not available to regular WhatsApp users.
Currently only available for Android, the service may be coming to Windows Phone, as hinted by a tweet by Nawzil, an ex-Microsoft MVP.
Testing "WhatsApp Business" for the first time.
— Nawzil (@Nawzil10) April 6, 2018
The news is not confirmed, but WhatsApp has been unusually supportive of Windows Phone, updating their app with the newest features well after other companies have abandoned the platform.
WhatsApp is owned by Facebook has currently has more than 1.5 billion users.
Update: The ever-reliable WABetaInfo denies that the app does, not in fact, exist:
This is the “BIZ section table”, visible in the normal WP app in “Contact Info” (as “Business Info” recently renamed).
No WhatsApp Business for Windows Phone platform is found in the server 🙂
— WABetaInfo (@WABetaInfo) April 7, 2018