LoopMessage - LoopMessage is a perfect macOS tool for personalized mass messaging via iMessage/SMS, WhatsApp, Facebook Messenger, Telegram, Viber, and Skype.
Twilio - Brings voice and messaging to your web and mobile applications.
IG MASS DMS - Seamlessly reach any target audience by using our mass dm software.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
TextBlast Bulk SMS - Send personalized mass messages easily
BulkSMS - SMS messaging service provider offering two-way SMS communication services.