Twilio - Brings voice and messaging to your web and mobile applications.
MirrorFly - World's Most Scalable Voice, Video & Chat SDK for Small, Medium & Enterprises
Plivo - Plivo simplifies your customer engagement.
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
Bandwidth - Bandwidth offers SIP trunking, Emergency communications, and Voice & Messaging APIs.
TalkJS - TalkJS is a messaging API enabling users to add buyer-seller chat to their online marketplace or platform.