Immediately get started creating a high quality game then publish native executables for both Microsoft Windows and Mac OS X or upload straight to Steam Workshop with a resource limited free version of GameMaker: Studio. Steam shop has also started offering software rather than just games..
This looks too good to be true. So you can make games and test games for everything, you just can’t publish them (export them) unless you pay the 500$.
It’s a limited demo.. you can make .exe for windows and macintosh with limitations. For making games for iOS, Android and HTML5, you have to buy the commercial version. Btw there are other alternatives both free and commercial to make games.
http://www.yoyogames.com/gamemaker/studio/free