A Guide for Voice API for Developers

Posted on October 15, 2022

Integration of telephony services into computer programs is taking off. Research firm 360 Research Reports released a forecast for the industry that predicts a growth rate of 18% per year from 2020-2026. With many companies now offering a voice API for developers, integrating voice technology in the development process has become much more manageable.

This article will tell you what you need to know about voice API. We’ll discuss the basics of what one is, what types of features you can integrate with your software, and how to choose a quality communications API provider.

What Does a Voice API for Developers Do?

A voice API allows developers to integrate the ability to make and receive calls into their company or client’s software projects. Although many aspects of development can be readily recreated from scratch, telephony services require significant expertise and carrier support. With a voice API, your team doesn’t have to worry about the backend telephony specifics. You’ll simply call a few API commands and instantly have your software connected via the internet to a Public Switched Telephone Network (PTSN). 

Voice API Use Cases

The only limit to how you can use a voice API in your projects is your imagination. Companies today are finding new and innovative ways to use the features offered by telephony services, and with voice APIs now making it easy to integrate the technology into software, you can efficiently and effectively make it a reality. Some common use cases are listed below to give you some ideas of what can be done.

  • Interactive voice response – When a customer calls into the business, you can program a custom interactive voice response to gather information about their reason for calling and route their call to the appropriate department or team member. Additionally, you can provide them automated answers to common questions to save the staff time and eliminate the need for the customer to wait on hold. 
  • Call transcription – It can be helpful to have a transcription of calls made to the staff. This could be for employee evaluation or training purposes, to better examine customer sentiment, or many other reasons. With the many cloud-based, speech-to-text platforms software can pipe into, a voice API for developers makes creating such transcriptions a breeze. 
  • Unified communications – Another common use for transcribed calls is to create a unified communications platform. With a voice API, you can have all of your company or client’s calls from a given customer transcribed and stored along with emails, social media messages, and other channels of communication. This makes it easier for staff members to get a full picture of the customer and better serve their needs.
  • Call tracking – Print and display advertising can be notoriously difficult to track. Marketers have been spoiled by the easy analytics of digital ads. But by assigning a separate number to each marketing campaign and tracking them with a voice API, a company can collect detailed information about which of their billboard, poster, and print ads are performing most effectively.
  • Private communications – Using a voice API, calls between two individuals can be facilitated through software that allows them to communicate but still keeps their private numbers hidden from each other.

Related: The Benefits of Self-Service Telecom Models

Common Voice API Features

Although the use cases above are common, the features provided by a good voice API for developers will allow you to do nearly anything you’d like to do with the voice after the API has connected it to your software. Below is a list of some of the most common features you can expect to find in a voice API solution.

  • Make outbound calls – As one of its most basic functions, every voice API will allow you to programmatically make an outbound call. After creating the call, you’ll have an object that can easily be queried and managed. This will allow you to continue to interact with the call and connect it to other parts of the voice API or your code.
  • SIP connectivity – As a middleman layer between your existing SIP infrastructure and your code, a good voice API will allow inbound calls to be received in much the same way you set up an outbound call. Now, you can connect calls coming from both directions to the software and develop more feature-rich applications. 
  • Intelligent call routing – Nearly every call center requires call routing. From something basic to a full-fledged smart IVR, a voice API will provide you with the tools needed to route calls using whatever logic is available in your programming language. This means your call routing solution can be highly customized to the needs of your company or client.
  • Media streaming – A typical telephone call is between the person making the call and whoever is on the other end. With media streaming, voice APIs let you split the audio off and stream it in real-time over the internet to whichever third-party tools you’d like. You can create a call-in show, send the audio to a conversational AI to talk to the caller, monitor voice biometrics during the call, and more. 
  • Conferencing – Armed with the tools we already mentioned, it wouldn’t be too hard for your team to put together a product that can handle conference calls. However, most voice APIs for developers are going to offer this functionality built-in. This saves you from having to reinvent the wheel and allows you to focus your development efforts on what makes the software you’re creating unique.
  • Text-to-speech – Many voice APIs will provide their own text-to-speech (TTS) service. This allows you to create dynamic interactions with callers without the need to have a person on the other end of the line. You can relay specific information about their account and other personalized information through a TTS provider. You can also hook into third-party TTS systems such as Amazon Polly, Microsoft Azure, or Google Cloud Services.
  • Call recording – Recording calls for quality and training purposes is something companies have been doing for a long time now. With a voice API, developers can take this process into their own hands. After recording the data, it can be sent out to be transcribed, stored in a data lake for later processing, and more. 
  • Answering machine detection – With the ability to detect the difference between a voicemail box and a live caller, voice APIs give you the opportunity to improve the experience of call recipients. Automated calls can respond differently depending on which of the two is answering the phone. 

What to Look for in a Voice API

There are many voice API providers on the market now, each hoping to take advantage of the explosive growth in the programmable telephony field. Picking the right API will help your development process go smoother and ensure that things remain smooth long after you’ve launched. Here are a few things to look for when choosing a voice API for your project:

  • Language support – The first thing to check for is whether or not the API supports your favorite language. Most voice APIs are based on REST, meaning any language that can access the internet can use them. However, providers often include custom libraries for popular languages to save your team some setup time. 
  • Documentation – Needing to perform a task but not knowing what function to use or not understanding what parameters the function takes can be frustrating, and finding the answer can be time-consuming. Good documentation avoids that hassle altogether, so be sure to look at the docs for your API candidates to see how complete they are.
  • Ease-of-use – An API could have the most complete documentation possible and still be a hassle to use. Good API design will reduce the amount of time it takes for you to build functioning code and improve your ability to iterate and debug your project as it grows. 
  • Scalability – When you choose a voice API, you’re also choosing the backend that the provider uses to power it. Be sure to check what plans they have in place for scalability. If your project grows to have a large number of users, will the provider’s servers be able to handle it? You don’t want to have to rewrite code for a new API because you’ve outgrown your current one.
  • Developer support – During the lifecycle of your product, problems may come up with the API. Maybe the servers will go down, or an endpoint in the API begins returning unexpected values. Whatever the problem is, you need it resolved quickly. Don’t trust your company’s communications system to a provider that will leave you waiting forever on support.
  • Fraud prevention – With any network-enabled technology, the chances of fraud are non-zero. Having an API that provides you with fraud protection will help prevent your communications system from being used in a way that can damage your business or harm your customers.

Related: How to Find the Right Managed Service Provider for Your Business

Let a Voice API Maximize Your Time and Effort

Flowroute offers a full range of telephony APIs, from voice to SMS to phone number management and beyond. Our APIs were designed by developers with other developers in mind and with a goal of making them powerful, flexible, and easy to integrate. We have libraries for the most popular programming languages, or you can connect directly to our REST API with your language of choice. Contact our sales team today to find out more about how Flowroute can help with your communications needs.