Twilio - Brings voice and messaging to your web and mobile applications.
E-goi - Email Marketing companies, SMS Marketing, software email marketing.
Plivo - Plivo simplifies your customer engagement.
Maytapi - Serverless Whatsapp Api with Chat and Agent support.
smooch - Smooch connects your business software to all the world’s messaging channels for a more human customer experience.
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.