Voice API is referred to as a tool that allows software developers to integrate calling features using an Application Programming Interface (API). Developers build a chat app with voice functionality and Voice APIs let these apps make and receive phone calls acting as a bridge to PSTN (Public Switched Telephone Network).

List of Top 10 Voice APIs Providers for Android ,iOS and Web Apps
CONTUS MirrorFly Voice Call API
Plivo API
Vonage API
Twilio API
EnableX API
MessageBird API
and more...

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