LoopMessage - LoopMessage is a perfect macOS tool for personalized mass messaging via iMessage/SMS, WhatsApp, Facebook Messenger, Telegram, Viber, and Skype.
Texted.io - Send text blasts to groups, receive individual replies
SuperDMs - SuperDMs helps you grow your following by sending bulk DMs to your tweet responders.
Text Blaster - Send thousands of text messages with one tap on Android
Promote Route - A Better WhatsApp™ Experience
WhatsMany - Send personalised WhatsApp messages in bulk