A free app for Android, by Farbflut Entertainment GmbH.

Mafia Empire City of Crime is a free real-time strategy game that lets you fight against other players in multiplayer and single-player modes. The game lets you build your own mafia and expand your territory in the city of crime. You can attack other players or work together with them to fight against the other mafia gangs. 

You can work with other players in the game. If you are in a situation where you need help, you can ask for help from players. They will help you if they can.