Sonic Rumble must be installed after the Google Play Games launcher is installed.

■How to install the Google Play Games Launcher
▪ Go to https://play.google.com/googleplaygames
▪ Download the Google Play Games installer from the [Download Beta Version] link.
▪ Launch the installer and follow the on-screen instructions to install Google Play Games.

■How to install Sonic Rumble
▪ Launch Google Play Games.
▪ Type "Sonic Rumble" in the search bar on the left.
▪ Select "Sonic Rumble" from the search results and install it.