Charlie Stigler, Angel Investor

Charlie Stigler is the co-founder of Tenor, an AI platform for leadership development launched in 2023. Tenor helps professionals practice difficult conversations with realistic voice AI characters and provides instant feedback to improve communication skills. He is also the creator of SelfControl, a widely used Mac application for focus and study, which he has maintained since 2009. Earlier in his career, Stigler spent six years at Workday, where he worked on blockchain-backed digital identity, credentialing, and product innovation, and co-founded Zaption, an interactive video learning company acquired by Workday. As an angel investor, Stigler backed Rubie in 2024, reflecting his interest in early-stage ventures that combine technology with practical applications in productivity and personal development.