2D+3D Unity Engine Manuals Unity is a cross-platform game engine developed by Unity Technologies which is primarily used to develop video games and simulations for PC consoles mobile devices and websites. First announced only for OS X at Apple's Worldwide Developers Conference in 2005 it has since been extended to target 27 platforms IOS Android Web and more in this app you can find manuals for all features if you looking for manauls for Unity to make a game this app can help you begin your first game.