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Best Telephony & Transport Tools for Voice AI
Phone numbers, SIP trunking, WebRTC and real-time media transport that carry the call.
UNIO EDITORS’ PICKS
Telephony & Transport
#1
Exotel
Voice API pioneer; CPaaS plus contact-center (Ameyo) and conversational AI (Cogno AI).

#2
LiveKit
Open-source WebRTC infrastructure and Agents framework for realtime voice and video AI.

#3
Plivo
Global CPaaS for voice, SMS, WhatsApp APIs in 190+ countries.

#4
Twilio
Programmable voice, phone numbers and SIP trunking used across most voice agent stacks.











