Clickteam Fusion 2.5 was developed by Clickteam, a French-based company that specializes in game development software. The software was first released in 2003 under the name "The Games Factory," and has since undergone several updates and revisions. The current version, Clickteam Fusion 2.5, was released in 2013 and has become one of the most popular game development software tools on the market.