Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
Tellephant - Helping you build incredible chatbots and integrate WhatsApp, Google, Facebook, SMS and more to your communication stack in seconds. All at the cheapest rates out there.
Twilio - Brings voice and messaging to your web and mobile applications.
Atomic SMS Sender - Free bulk SMS software to send bulk text messages from PC
InstaChabot.io - Build Instagram Chatbot For Shopify - Absolute Reason for Your ROI Growth
Clickatell - Simple, reliable mobile messaging cloud.