Content Rated 6 Russian pyramid, also known as Russian billiard (Russian: ру́сский билья́рд, russky bilyard) or pyramid billiards, is a cue sport that has several differences from Western pool, although game play is still dominated by attempts to pocket (pot) billiard balls. It is played in Russia and also in countries of the former Soviet Union. A variant with colored balls modeled on those of Western pool is called Russian pool. Another variant, kaisa, is popular in Finland.

Make sure that third-party apps are allowed on your device: go to Menu->Settings->Security-> and check "Unknown Sources"

Tap the APK file. Allow the app any required permissions it asks for. Then, at the bottom of the installer window, click INSTALL.

You'll see a confirmation the app is installed. Now you'll see the app available in your list of installed apps.