​In the last couple of years, CPaaS providers have sprung up to take advantage of the API driven programmable web interfaces to offer telephony services over the cloud. In their earlier avatar, some of them were known as Cloud Telephony services. However, CPaaS has a much broader scope than merely offering telephony service over the cloud.
​With the advent of VoIP in the early 2000s, companies started offering voice telephony services on the Internet. Along with the amalgamation of cloud computing over the Internet, companies started building various specialized services, one of them being real-time media communication. And thanks to the REST APIs and the advancements in the tech stack, it is now possible to offer these services via a programmable API interface.
​In this blog post, we are going to explore the various CPaaS providers and platforms which are offering top-notch communication services over cloud. These services range from simple use cases such as voice/text messaging to more complex applications that require call routing, streaming, and multi-party communication facilities. ​
Here is our list of the top CPaaS providers.
If your company is looking for a CPaaS platform, you have to make a choice based on the plethora of feature set ranging from SMS, FAX, voice video and more. To help you make an informed choice, we have considered several key features of the prevailing CPaaS platforms.
​Features For Evaluating CPaaS Platforms
FEATURE | Description |
|---|---|
1. Voice | CPaaS supports voice calls and voice based services such as voice messaging, notifications and broadcast |
2. Video | CPaaS supports video calling and conferencing services |
3. SMS | CPaaS supports SMS services |
4. Messaging | CPaaS supports messaging services for app to app communication and real-time notifications |
5. Email | CPaaS supports Email services |
6. Fax | CPaaS supports Fax services |
7. M2M | CPaaS supports communication with IoT devices |
8. Contact Center | CPaaS supports hosted contact center service for inbound and outbound call handling |
9. Virtual Phone Numbers | CPaaS supports virtual phone numbers |
10. AI Engine | CPaaS supports AI capabilities such as conversational bots, TTS (Text-to-Speech), STT (Speech-to-Text) and other intelligent features |
11. Call/Session Control | CPaaS supports granular call or session control such as forwarding, rejection, recording, transfer, tracking and more. |
12. Supported Languages | Supported programming languages by the CPaaS SDKs |
Feature Categories
The above features are categorized into three categories
- 1Common Communication Features ( 1 - 7)
- 2Enhanced Features (8 - 11)
- 3Programming Languages (12)
The following symbols represent the availability and level of API customization for a given feature.
Symbol | |||||
|---|---|---|---|---|---|
Meaning | Feature Supported | Feature Not supported | Supported with basic customization | Supported with intermediate customization | Supported with advanced customization |
1. Twilio
Twilio is by far the most comprehensive CPaaS service provider available in the world. Founded in 2008, Twilio has built a very robust product portfolio of communication services starting from voice, SMS and video. Over the years they have added more services and features to their core CPaaS offerings. As a result, now you can use Twilio services to initiate email communication as well as IoT based data exchange.
Twilio Flex is a powerful contact center suite for voice, video and messaging based collaboration. It is fully programmable and has inbuilt customization for designing your own interaction flows with customers.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
Twilio supports C#, Java, Node.js, PHP, Python, Ruby. It also has iOS and Android SDKs
2. Plivo
Plivo currently supports SMS and Voice APIs. If you are only looking for enhanced voice and SMS based features then Plivo is a good choice. Plivo also provides virtual phone numbers of various types and offers SIP trunking solution for deploying call center ​infrastructure.
PHLO is Plivo's drag and drop interaction editor which lets you design your voice and SMS interaction flow as per your business requirement. It is ideal for building specific communication workflows such as SMS surveys and IVR.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
Plivo supports PHP, Node.js, Ruby, Java, .NET, Python, GoC#, Java, Node.js, PHP, Python, Ruby. For building client applications it has browser SDK as well as iOS and Android SDK.
3. Exotel
Exotel is also a CPaaS service focused on Voice and SMS. Together with virtual phone numbers, it offers all the standard services such as on call handling, call recording, SMS and call campaigns and some interesting ones, such as missed call service.
Exotel also supports building custom workflows around voice and SMS conversations. Known as Applet, it is a web-based interface for adding interactive features to a conversation, such as greeting messages, password enforcement, additional data gathering through number pad.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
Exotel only has REST APIs. The official developer portal does not list any SDKs.
4. Xoxzo
Xoxzo is a no-frills voice and SMS centric CPaaS service. Xoxzo is an excellent choice for essential voice call handling with outbound calls, dial-in call handling and a utility API for looking up carrier information. Even with its simple set of services, Xoxzo still offers conference calls which is a great feature to have for anyone starting with a CPaaS provider.
Xoxzo also supports virtual numbers but it is currently only available in Japan and Malaysia for incoming calls.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
Xoxzo supports Python, Ruby and PHP.
5. Nexmo
​Nexmo offers voice, video, SMS and messaging API for a unified communication experience. Nexmo also has SIP trunking solutions for customized call routing and PBX/ACD compatible services. Nexmo also provides virtual phone numbers and has a shortcode feature for provisioning short, campaign-specific numbers for better branding.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
​Nexmo supports Ruby, PHP, Python, .NET, Node.js, JAVA along with iOS and Android SDK and a Javascript SDK for the browser.
6. Knowlarity
​Knowlarity is an AI-enabled voice-centric CPaaS platform. It is projected as a cloud based intelligent virtual PBX system for call center operations. However, through the PBX, It is also possible to host point to point calls. Knowlarity also supports text to speech and speech recognition capabilities along with industry-specific smart IVR conversations.
​Knowlarity's PBX service is offered under the name "Super Receptionist API". In addition to the call and notification APIs, Knowlarity also supports an agent API for building virtual agent interfaces for handling incoming calls for ​CRM operations.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
Knowlarity supports REST APIs. No SDKs are available.
7. Kaleyra
​Extending ou​r list of voice and SMS focussed CPaaS providers, Kaleyra is yet another option that you can consider. Kaleyra has all the usual features of voice and SMS based interactions. Kaleyra Hexa is the unified platform for building custom conversations with a flow builder, contact and campaign management features.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
Kaleyra supports REST APIs. No SDKs are available.
8. Ring Central
​Ring Central is a comprehensive CPaaS solution and supports, voice video, messaging, SMS as well as Fax. After Twilio, it is the most feature-rich CPaaS platform available. Ring Central has solutions catering to small businesses and enterprise separately. It also provides ready made services for specific use cases such as ​team messaging, video meeting and hosted contact center management.
​Ring Central has an impressive list of integrations with many office , productivity and CRM solutions and supports omnichannel interactions through its platform.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
​Ring Central supports .NET, Java, Javascript, PHP, Python, Ruby SDKs. It also has iOS client SDK and a special WebRTC library for building browser based client applications.
9. EnableX
EnableX is the new kid on the block. EnableX is a video communication as a service platform and also has flexibly deployment options for self hosting the platform either on private cloud or on-premises.
EnableX APIs are modeled on the concept of a chat room. However, instead of chat, these rooms represent a RTC session. Multiple users can then join this room and interact with others through voice, video and messages.
Common Communication Features
Voice | Video | SMS | Messaging | Fax | M2M | |
|---|---|---|---|---|---|---|
Enhanced Features
Contact Center | Virtual Phone Numbers | AI Engine | Call/Session Control |
|---|---|---|---|
Supported Programming Languages
EnableX supports Python, Node.js, Java, Ruby, PHP, .NET and Go. It also has SDKs for web, Android and iOS.
