Use APKPure App
Get Click to Chat - Open a Chat old version APK for Android
Chat with any mobile number without saving it in your contact list.
Click To Chat allow you to open a chat with any mobile number without saving it in your contact list. If you want to send a message to some unknown person without saving the contact.
No one contact is created on your phone contact list.
Disclaimer:
-----------------
This app is not related to WhatsApp Inc. This app uses the public API provided by WhatsApp to open a chat with any number.