This story is available exclusively to Insider subscribers. Become an Insider and start reading now. After one year, audio-only social app Clubhouse is reportedly in talks for a $4 billion valuation. But this is not the first buzzy app that cofounder Paul Davison created. On "How I Built This," he talked about the rise and fall of Highlight, his social app from 2011. During a year without bars or parties, the tech social scene moved onto Clubhouse. The audio-based social app is only a year old but has already won over Silicon Valley and is in talks for a $4 billion valuation, according to Bloomberg.