See MobControl in action by downloading the beta version of RetroWar: 8-bit Party Battle Defeat up to 15 of your friends in a tournament of 80s-inspired retro mini games.

Use mobile devices as game controllers.

The server requires Java 1.8+. The clients can be any system with a web browser, but ideally a mobile phone running Android or iOS.

./gradlew run

buildscript{
    repositories {
+        jcenter()
    }

    dependencies {
+       compile "uk.co.electronstudio.mobcontrol:mobcontrol:0.1.+"
    }
}

MobControl is distributed under GPL+Classpath license, the same as OpenJDK itself, so you will have no problem using it anywhere you use OpenJDK.