Drift - A messaging app that helps you grow your business.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
Tars - TARS enables users to create chatbots that replaces regular old webforms.
Plivo - Plivo simplifies your customer engagement.