Send a WhatsApp direct without adding to your contact list
Just fill in the phone number you want to WhatsApp in international form e.g. +1 650 555 7475
Tap and add to homescreen to install this service as a web app
How to send WhatsApp message without saving the phone number? That is what this WhatsApp direct service is for. If you want to sent a WhatsApp message without going to the trouble of adding someone to your contact list or saving their number in your address book. You just don't want to bloat your contacts with everyone you ever have sent a WhatsApp message. This service is for you:
NCA - nocontactapp - lets you send WhatsApp messages to unkown contacts.
Also using Signal, SMS or iMessage? Try gotext.us