Micropolis - Micropolis is the open source version of SimCity Classic from Maxis, developed by Will Wright and Don Hopkins.
Cities: Skylines - Cities: Skylines is a Construction and Management, City Building, and Single-player Simulation developed by Colossal Order and published by Paradox Interactive.
Cytopia - Cytopia, the free opensource citybuilding game
SimCity BuildIt - Build, craft, and control! SimCity BuildIt is an all-new SimCity game designed just for mobile.
Citybound - Open-source city building sim with a focus on realism through microscopic details
Citystate - Citystate is a Futuristic, Strategy, City Building, Indie, Sandbox, and Single-player video game owned by Andy Sztark.