Twilio - Brings voice and messaging to your web and mobile applications.
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
BulkSMS - SMS messaging service provider offering two-way SMS communication services.
Restcomm - Next generation cloud communication platform that allows for the easy building of voice, video, and messaging applications.
Plivo - Plivo simplifies your customer engagement.