Photon Raises $4.5M to Replace Mobile Apps With Messaging AI Agents

Summary

Photon raised $4.5 million in seed funding, co-led by Gradient and A*, with Vercel, HongShan, Z Fellows, Llama Ventures, Karman and angels participating. On September 17 in San Francisco, its tongue-in-cheek mobile app funeral put app icons in a coffin alongside developer panels from Vercel, Stripe and OpenAI. CEO Daniel Tian says apps will eventually give way to agents operating inside iMessage and WhatsApp, though the shift will take time. Meta’s No. 1 app, Muse, tests that install-fatigue thesis.

Photon grew from an open-source iMessage bot Tian built to reply as him, which thousands adopted on GitHub. He left UPenn’s M&T program, while co-founder and CTO Ryan Zhu left high school and later became a visiting student at MIT’s Media Lab. The pair had repeatedly struggled to get consumer apps discovered and saw Apple’s Messages as built-in distribution. Open-source Photon still represents 98% of use. Launched in April, the managed subscription platform provides 99.95% uptime, SOC 2 Type II and HIPAA compliance, with a unified API, extensible channel framework, CLI and observability for iMessage, WhatsApp, Telegram, SMS, RCS, email, voice and more.

Photon reports over 40,000 developer sign-ups, 10x revenue growth in four months, under 3% churn and 5x messaging growth in the last month, but does not disclose revenue. Usage beyond 10 users requires one of three paid tiers. Customers include Corgi Insurance, Boardy, Ditto, Rho, Fliptexts and Slashy. Integrations include Vercel’s Eve and ChatSDK; Nous Research’s Hermes uses Photon as its default iMessage layer; Photon underpins Tencent’s QClaw and NanoClaw, alongside LangChain, Mastra, Convex, Render, Railway and Telnyx integrations. Tian estimates deployments reach millions of end users and sees Photon becoming an agent-to-agent-to-person layer that recruits services such as flight and hotel booking agents.