Dawson Chen co-founded Letterbook (YC S23), an AI-native customer-support platform whose agent connects to a company's inbox and database to draft replies to every ticket for human approval. He also co-founded Martin, an AI personal-assistant app that grew to roughly 100,000 users, and since August 2026 has been Co-Founder and COO of Freebuff. Chen studied computer science and economics at Yale University.