# Callbook AI

> Callbook AI is a Y Combinator (S26) startup building AI voice agents that make and take business phone calls in English, Spanish, and Portuguese. Founded by Colombians Diego Avellaneda and Daniel Martinez, it began as a plug-and-play AI phone system for Zoho CRM and has sharpened its focus on automated debt collections and portfolio management across Latin America, handling calls, WhatsApp, SMS, and email from a single platform.

- **Founded:** 2024
- **Headquarters:** San Francisco, United States (originally Bogota, Colombia)
- **Founders:** Diego Avellaneda (Co-founder & CEO), Wilson Daniel Martinez (Co-founder)
- **Team size:** ~10
- **Products:** Callbook AI Voice Agents, Callbook.ai for Zoho CRM, Multi-channel outreach, AI Collections Platform
- **Notable:** Selected for Y Combinator's S26 batch, Recognized as one of the Colombian AI startups entering YC, Featured on Product Hunt for its Zoho CRM AI phone system

## Products & services

- **Callbook AI Voice Agents** — AI phone agents that make and receive human-like calls for collections, lead qualification, appointment confirmation, customer loyalty, sales, and support, with configurable accent, tone, and call scenarios.
- **Callbook.ai for Zoho CRM** — End-to-end AI phone system integrated with Zoho CRM - calls trigger from CRM workflows, and conversation data is transcribed and written back to specified CRM fields automatically.
- **Multi-channel outreach** — Coordinated customer contact across phone calls, WhatsApp, SMS, and email from a single platform.
- **AI Collections Platform** — Debt-collection workflows covering the full timeline - preventive reminders before due dates through recovery of obligations delayed up to 90 days, with real-time payment-commitment capture.

## Achievements

- Selected for Y Combinator's S26 batch
- Recognized as one of the Colombian AI startups entering YC
- Featured on Product Hunt for its Zoho CRM AI phone system
- Participated in Starco 2025 in Medellin and generated significant new leads
- Accepted into the AWS Startups program

## Latest updates

- **2026-07** — Announced as part of Y Combinator's Summer 2026 (S26) batch.
- **2026-06** — Sharpened positioning toward AI-powered debt collections and portfolio management across LatAm.
- **2025-01** — Expanded from a Zoho CRM phone add-on to a multi-channel voice platform (calls, WhatsApp, SMS, email).

## Links

- Website: https://callbook.ai
- LinkedIn: https://www.linkedin.com/company/callbook-ai

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Profile page: https://yespress.io/callbook-ai-yc-s26
Published by YesPress — https://yespress.io
Last updated: 2026-07-31