Well, Microsoft has acquired the entire "Gears of War" franchise from Epic Games. That means Gears of War, Gears of War 2, Gears of War 3, Gears of War: Judgement are all properties of Microsoft, and this means future Gears of War titles is all exclusive to Microsoft products - Xbox 360, Xbox One or any other future project Microsoft may have in the pipeline. This opens Gears of War to PC, tablets, phones, or any other device Microsoft wants it on.
http://news.xbox.com/2014/01/games-microsoft-studios-gears-of-war
http://news.xbox.com/2014/01/games-microsoft-studios-gears-of-war