Gamasutra sister publication Game Developer magazine has released the results of its first-ever mobile and social developer technology survey in the May 2012 issue. (The May 2012 issue is now available via subscription and digital purchase.) Unsurprisingly, iOS was the most popular development platform, with 94.6% of surveyed developers releasing games for iOS, followed by Android (70.7%), Windows Phone 7 (8.8%), BlackBerry OS (2.7%), Symbian (2.0%), and Samsung Bada (1.4%). Of those iOS developers, 39.4% targeted devices running iOS version 4.1 and above, compared to 30.7% targeting iOS version 5.0 and above, 16.5% aiming for 4.0 and above, and 13.4% developing for version 3.0 and up. Unity topped the list of mobile game engines, with 53.1% of developers reporting using Unity compared to 39.8% using a custom engine., 17.7% using Cocos2D, 5.3% using Marmalade, and 5.3% using Corona (this question wasn't exclusive, so the percentage count adds up to more than 100%). When it comes to determining which engine features are most important for a developer, "Rapid development time" was ranked as the most important factor, followed by "Flexibility and easy extendability," "Engine performance," "Support and documentation," and "Prior successful use by another team," respectively. The full mobile/social tech survey offers more detail about mobile game tech usage, platform and device support, and more. The May 2012 issue of Game Developer also features a postmortem for Zynga's Indiana Jones Adventure World, a deep dive into TERA's free-targeting combat system, and more. You can purchase individual Game Developer issues or a subscription from the Game Developer web store, or download the Game Developer iOS app.