Postscript

Twilio offers developers a powerful API for phone services to make and receive phone calls, and send and receive text messages. Their product allows programmers to more easily integrate various communication methods into their software and programs.

Nexmo connects your apps directly to carriers around the world. Integrate SMS and Voice messages using one simple API. Use Nexmo Verity to register users, verify transactions, and implement two factor authentication.

Braze is a comprehensive customer engagement platform that powers relevant and memorable experiences between consumers and the brands they love.

Agora.io provides building blocks for you to add real-time voice and video communications through a simple and powerful SDK. You can integrate the Agora SDK to enable real-time communications in your own application quickly.

Plivo provides basic building block APIs in the form of Plivo XML and HTTP API, to create telephony apps, so developers can completely do away with learning the nitty-gritty of the telephony plumbing.

At MessageBird we believe that communicating with a business should feel as natural as communicating with a friend. That's why our SMS, Voice and Conversations APIs continue to revolutionize company-customer interactions.

It adds the clarity and emotion of face-to-face communication to your brand whether you're developing for the web, iOS, or Android. We make the integration of high-quality live video a breeze so that you can focus on building a great product.

It is a global leader in omnichannel engagement. We help our clients and partners overcome the complexity of consumer communications & grow their business.

A Communications Platform as a Service company offering a full suite of voice, messaging, and 9-1-1 APIs, all built atop the company's own all-IP voice network.

BulkSMS.com is a leading SMS messaging service provider offering two-way SMS communication services. The BulkSMS gateway reaches across borders and connects to over 800 mobile network operators world-wide.

Tropo is a powerful yet simple API that adds Voice and SMS support to the programming languages you already know.

It is a cloud telephony platform that powers communication for enterprises, startups and small and medium enterprises in India and Southeast Asia. They provide APIs that help companies devise their own communication flow.

It is a cloud communication platform offering powerful messaging solutions to empower business communications. It provides bulk SMS service provider offers transactional & promotional bulk SMS solutions to enterprises via powerful & robust bulk SMS gateway internationally.

Reach your customers in a matter of minutes with our instant delivery. Find a Bulk SMS API for every application/technology.

VoxImplant is a communications cloud platform built and designed for developers. Use the VoxImplant mobile SDK, telephony integration, or web sdk to build anything from softphones, click-to-call, automated surveys, cloud contact center or PBX, to cloud IVR and call tracking.

It gives powers to chat commerce by helping you reach and engage customers through SMS, WhatsApp and other social channels.

Create a better customer experience with SMS, Chat Apps, Video Interaction & Voice. It’s integrated communications platform as a service (CPaaS) streamlines multiple communications channels into a single dashboard.

It is a business mobile messaging service provider that enables businesses of all sizes and industries to deliver and manage SMS text messages from PC, web, email or API.

Pushnami enables you to capture your audience, intelligently market to them across web, mobile, and email, and grow your revenue. Streamline your messaging strategy with features like machine learning,automated drip campaigns, and customize

Send and receive SMS globally with the SMS gateway. Trust your business messaging with reliable, direct routes, and lightning fast message delivery.

It is an Open Source, low-latency and high-quality voice-chat program written on top of Qt and Opus. There are two modules in Mumble; the client (mumble) and the server (murmur). The client works on Windows, Linux, FreeBSD and macOS, while the server should work on anything Qt can be installed on.

Quickly add Voice, Video, SMS to your web and mobile applications. It is a communication platform which provides APIs that help clients quickly add Voice/Video/SMS to any application.

Voice broadcasting and text messaging with Call-Em-All's automated messaging service for groups and organizations of all sizes.

It is a plug and play app, to send & receive, single or bulk SMS, MMS , WhatsApp, Telegram & CTI from salesforce.

It is a perfect communication platform that enables businesses to connect, engage and interact with their users with help of its SMS, Voice and APIs.

It is a sales productivity phone service that makes all of your calls searchable, trackable, and archived in your CRM sales.

Revolutionary SMS Platform that Has Proven to Deliver 10x Better Results than a Traditional Email Auto-Responder. It is the Most Powerful SMS Platform For creating and managing text message campaigns with your subscribers and customers

Build a full text marketing program in minutes without writing any copy or code

Get free SMS verification codes for online accounts or rent a private number for enhanced privacy. Worldwide coverage including USA, UK, Canada, and more. Secure, reliable, and easy to use.

Dial in by phone or computer with up to 1,000 callers and experience HD quality sound during each conference call.

It allows you to build fully customizable voice and chat apps that work in the browser. And it even comes with 4 open source templates that help you get started.

Transact via video, image, audio text messages

Traditional calls and meetings monopolize your time and require endless scheduling. It is personal, asynchronous communication built for remote teams.

It is an automated Text Messaging Software for your business to automate your hustle. Convert your leads into customers with automated Drip Campaigns.

It is a cloud communications platform that empowers businesses to integrate voice, messaging, and video communication into their applications and services.

It allows you to reach your customers via SMS over It's own connectivity to global mobile networks. It provides reliable and cost-effective SMS services to businesses across all industries and aims to connect all countries and territories via direct connections.