Social Discovery Startup Sonar Shuts Down

Sonar, an app which helped users meet and discover “interesting people in the world” via smartphone, has closed its doors, according to CEO Brett Martin. The app, which raised around $2 million from angel and VC investors and received no shortage of press attention, was briefly popular — it had millions of installs — before languishing over time. Martin’s long post-mortem can be found on the blogging platform Medium.