Grand Ages: Medieval is described as 'real-time strategy game. Lead your people and advance through the decades by utilising construction, research, expansion and conquest in an area extending from Scandinavia and North Africa; to Portugal, the Caucasus and the Middle East'. There are four alternatives to Grand Ages: Medieval for a variety of platforms, including Linux, Windows, Mac, Android and BSD. The best alternative is 0 A.D., which is both free and Open Source. Other great apps like Grand Ages: Medieval are openage (Free, Open Source), CaesarIA (Free, Open Source) and Land and Castles (Freemium).
0 A.D. is a free, open-source, cross-platform real-time strategy (RTS) game of ancient warfare. In short, it is a historically-based war/economy game that allows players to relive or rewrite the history of Western civilizations, focusing on the years between 500 B.C. and 500 A.D.
CaesarIA is an open source remake of Caesar III game released by Impressions Games in 1998, it aims to expand the possibilities of the classical city-building simulators and to add new features showing the city life. Now the game work with Windows, Linux, Mac, Haiku and Android.