https://www.cnet.com/news/smule-is-the-biggest-music-app-you-never-heard-of/

Smule wants everyone to know its name. 

The company, a San Francisco-based startup named from a portmanteau of "sonic" and "mule," runs a collection of music-related apps. The biggest by far is "Sing! Karaoke," an interactive singing app with people belting out 20 million songs with each other daily.