Android Controllers and Players outside the Playstore

Hi,
I am aware of the multitude of Apps available through Google but I have not arrived at an App that I can install on a Google free Tablet.
I guess you can simply create a shortcut on the desktop and point this to the IP-address of your LMS. But what about a player?
Wasn't there once an official Logitech App? Where has it gone? It should be available through their homepage?