Limitations

This App is compatible with Salesforce Lightning and it is not Salesforce Classic.
This App is compatible with Desktop Only . It is not Mobile friendly
This SFDC packaging Org doesn’t support patch releases.
File Size while sending media files is limited to 4.0MB.
There is no API to update Opt In numbers in Bulk, only the numbers which are already Opt-In will receive the messages.
There is no call back API implemented in this phase of rollout, thus the App will have the functionality of just showing outbound messages in the WhatsApp Message History Screen and not the received messages.
This app does not support inbound messages.
Media File Limitations