Click To Message

With this App you can send messages to a WhatsApp phone number without being saved in your address book.

It's free. No Ads.

This App use "Click to chat" feature, a public API of WhatsApp. Source: https://faq.whatsapp.com/general/chats/how-to-use-click-to-chat

DISCLAIMER: This App is not associated with WhatsApp. WhatsApp is a registered trademark of WhatsApp Inc.