Glossary · Automation & Integrations
Twilio
Overview
What Twilio is
Twilio is a cloud communications platform, often called CPaaS, that gives developers APIs to add messaging and calling to their own software. Instead of contracting with carriers and building telecom systems, a team uses Twilio to send and receive SMS and MMS, place and answer voice calls, message on WhatsApp, and send email through its SendGrid product. It also provides phone numbers and verification tools for two-factor authentication.
How Twilio works
Your application calls Twilio's API to send a message or start a call, and Twilio uses webhooks to notify your app about incoming messages, call events, and delivery status. Pricing is pay-as-you-go, billed per message segment, per call minute, and per phone number, so you pay only for what you use. Twilio Studio adds a visual, drag-and-drop builder for designing call and message flows without heavy coding.
How an agency uses Twilio
Twilio is the engine behind many of our messaging and voice automations. We use it to power AI voice agents that answer calls, send instant SMS replies to new leads, deliver appointment and booking reminders, and route customer service conversations. It connects cleanly to CRMs and automation tools through webhooks, so a text or call can update records, trigger follow-ups, or hand off to a live rep, tying communication into the rest of a client's workflow.
Where we use it
Related Zen in Tech services
How our team puts Twilio to work in real projects.
FAQ
Twilio — common questions
How much does Twilio cost?
Twilio uses pay-as-you-go pricing: you pay per SMS segment, per voice minute, and a small monthly fee per phone number, with rates varying by country. There is no large upfront commitment, so cost scales with usage.
What is Twilio used for?
Twilio is used to add SMS and MMS texting, voice calling, WhatsApp messaging, email, and phone-number verification to apps and workflows. Common uses include appointment reminders, two-factor authentication, alerts, marketing messages, and AI voice or chat agents.
Is Twilio only for SMS?
No. While Twilio is best known for programmable SMS, it also handles voice calls, WhatsApp, email via SendGrid, video, and identity verification, making it a broad communications platform rather than a single-channel texting tool.
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Knowledge hub
From our knowledge hub
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