Zibu is a healthcare-focused voice AI company headquartered in San Jose, California, founded by Avi Singh, a second-time entrepreneur and former Principal Product Designer at Moveworks. The company builds an AI-powered voice agent designed to handle after-hours patient communication, capturing clinically relevant information from incoming calls and relaying structured summaries to on-call providers via text or voice message. The platform integrates with electronic health records systems to enable appointment scheduling and prescription refill requests, and is HIPAA-compliant with proprietary AI guardrails designed to prevent medical advice generation and ensure accuracy in a regulated healthcare environment. Zibu's customers include private medical practices seeking to reduce missed appointments and improve patient responsiveness; the company targets a market worth $11.5 billion, addressing the estimated $150 billion in annual costs to the U.S. healthcare system from missed appointments. No public fundraising rounds have been disclosed as of May 2026.