Voice social network Clubhouse said on Sunday it will expand its Android app worldwide in a week, days after launching a beta version of its service on Google-owned mobile operating system for users in the U.S.

The startup, valued at about $4 billion, said it will roll out the Android app to Japan, Brazil, and Russia on Tuesday; Nigeria and India three days later, and rest of the world by Friday afternoon.

Clubhouse originally launched as an iPhone-only app last year. The app quickly gained popularity last year, attracting several high-profile celebrities, politicians, investors and entrepreneurs.

The startup began developing the Android app early this year and started to test the beta version externally this month. In a town hall earlier this month, the startup said availability on Android has been the most requested product feature.